{
  "title": "Bar Graphs (Data Handling) - Grade 8 CBSE",
  "total_questions": 100,
  "questions": [
    {"id": 1, "difficulty": "easy", "question": "What is a bar graph used for?", "options": {"A": "To show parts of a whole", "B": "To compare quantities for different categories", "C": "To show trends over time", "D": "To plot points on a coordinate plane"}, "correct_answer": "B"},
    {"id": 2, "difficulty": "easy", "question": "In a bar graph, the length of each bar represents its ___.", "options": {"A": "color", "B": "value", "C": "label", "D": "width"}, "correct_answer": "B"},
    {"id": 3, "difficulty": "easy", "question": "Which axis of a bar graph usually shows the categories?", "options": {"A": "x-axis", "B": "y-axis", "C": "z-axis", "D": "None of these"}, "correct_answer": "A"},
    {"id": 4, "difficulty": "easy", "question": "Which axis of a bar graph usually shows the frequency or quantity?", "options": {"A": "x-axis", "B": "y-axis", "C": "Both", "D": "Neither"}, "correct_answer": "B"},
    {"id": 5, "difficulty": "easy", "question": "The bars in a bar graph can be drawn ___.", "options": {"A": "only vertically", "B": "only horizontally", "C": "vertically or horizontally", "D": "only diagonally"}, "correct_answer": "C"},
    {"id": 6, "difficulty": "easy", "question": "What is the title of a bar graph used for?", "options": {"A": "To make it colorful", "B": "To describe what the graph represents", "C": "To label the axes", "D": "To count the bars"}, "correct_answer": "B"},
    {"id": 7, "difficulty": "easy", "question": "The space between bars in a bar graph should be ___.", "options": {"A": "different", "B": "zero", "C": "equal", "D": "very large"}, "correct_answer": "C"},
    {"id": 8, "difficulty": "easy", "question": "If a bar reaches the value 40 on the y-axis, what does it mean?", "options": {"A": "The category is 40.", "B": "The frequency or quantity for that category is 40.", "C": "There are 40 categories.", "D": "The scale is 40."}, "correct_answer": "B"},
    {"id": 9, "difficulty": "easy", "question": "What is the scale of a graph?", "options": {"A": "The number of bars", "B": "The difference between consecutive values on an axis", "C": "The color of bars", "D": "The width of bars"}, "correct_answer": "B"},
    {"id": 10, "difficulty": "easy", "question": "A double bar graph is used to compare two sets of data for the same ___.", "options": {"A": "scale", "B": "categories", "C": "title", "D": "axis"}, "correct_answer": "B"},
    {"id": 11, "difficulty": "easy", "question": "In a bar graph showing favourite fruits of students, the categories would be ___.", "options": {"A": "Apple, Banana, Mango, etc.", "B": "Number of students", "C": "1, 2, 3, 4...", "D": "Colors"}, "correct_answer": "A"},
    {"id": 12, "difficulty": "easy", "question": "If the scale on the y-axis is 1 cm = 10 students, a bar of 4 cm height represents ___ students.", "options": {"A": "4", "B": "10", "C": "40", "D": "14"}, "correct_answer": "C"},
    {"id": 13, "difficulty": "easy", "question": "Which part of the bar graph helps you read the exact value of a bar?", "options": {"A": "The color", "B": "The scale on the axis", "C": "The space between bars", "D": "The title"}, "correct_answer": "B"},
    {"id": 14, "difficulty": "easy", "question": "A bar graph is most similar to a ___.", "options": {"A": "pie chart", "B": "pictograph", "C": "line graph", "D": "histogram"}, "correct_answer": "B"},
    {"id": 15, "difficulty": "easy", "question": "To represent the population of 5 cities, which graph is most suitable?", "options": {"A": "Bar graph", "B": "Line graph", "C": "Pie chart", "D": "All of these"}, "correct_answer": "A"},
    {"id": 16, "difficulty": "easy", "question": "In a vertical bar graph, the categories are placed on the ___.", "options": {"A": "top", "B": "x-axis", "C": "y-axis", "D": "right side"}, "correct_answer": "B"},
    {"id": 17, "difficulty": "easy", "question": "What should all bars in a bar graph have?", "options": {"A": "Same color", "B": "Same width", "C": "Different heights", "D": "No labels"}, "correct_answer": "B"},
    {"id": 18, "difficulty": "easy", "question": "If data shows the sales of a shop over 12 months, a ___ bar graph can be used.", "options": {"A": "single", "B": "double", "C": "multiple", "D": "single or multiple"}, "correct_answer": "D"},
    {"id": 19, "difficulty": "easy", "question": "The difference between the highest and lowest values in a data set is called the ___.", "options": {"A": "mean", "B": "range", "C": "frequency", "D": "scale"}, "correct_answer": "B"},
    {"id": 20, "difficulty": "easy", "question": "True or False: In a bar graph, bars can touch each other.", "options": {"A": "True", "B": "False", "C": "Only in double bar graphs", "D": "Only if the data is continuous"}, "correct_answer": "B"},

    {"id": 21, "difficulty": "medium", "question": "The bar graph shows the number of books read by students in a month. If the bar for 'Anil' is 6 units high and the scale is 1 unit = 2 books, how many books did Anil read?", "options": {"A": "6", "B": "8", "C": "12", "D": "3"}, "correct_answer": "C"},
    {"id": 22, "difficulty": "medium", "question": "In a double bar graph comparing boys' and girls' marks in 5 subjects, how many bars will be there for each subject?", "options": {"A": "1", "B": "2", "C": "5", "D": "10"}, "correct_answer": "B"},
    {"id": 23, "difficulty": "medium", "question": "What is the range of the data represented by bars with heights 3, 7, 5, 9, 2 cm if scale is 1 cm = 5 items?", "options": {"A": "7 cm", "B": "35 items", "C": "9 cm", "D": "45 items"}, "correct_answer": "B"},
    {"id": 24, "difficulty": "medium", "question": "From a given bar graph showing sales from Mon to Fri, which day had sales 50% more than the lowest sales day?", "options": {"A": "Can be found directly", "B": "Cannot be found", "C": "Only if scale is given", "D": "Only if total is given"}, "correct_answer": "A"},
    {"id": 25, "difficulty": "medium", "question": "If the total number of students in a class is 50 and a bar graph shows 10 students like Science, what is the central angle for Science in a pie chart?", "options": {"A": "10°", "B": "36°", "C": "72°", "D": "90°"}, "correct_answer": "C"},
    {"id": 26, "difficulty": "medium", "question": "A bar graph has categories: A, B, C, D. The bar heights are 8, 12, 6, 14 units. What is the average height?", "options": {"A": "8", "B": "9", "C": "10", "D": "11"}, "correct_answer": "C"},
    {"id": 27, "difficulty": "medium", "question": "For data on temperature of 5 cities, which type of bar graph is most informative if you want to compare with previous year?", "options": {"A": "Simple bar graph", "B": "Double bar graph", "C": "Pie chart", "D": "Line graph only"}, "correct_answer": "B"},
    {"id": 28, "difficulty": "medium", "question": "In a bar graph with scale 1 unit = 20 people, a bar of length 3.5 units represents how many people?", "options": {"A": "35", "B": "55", "C": "60", "D": "70"}, "correct_answer": "D"},
    {"id": 29, "difficulty": "medium", "question": "The bar graph shows the favourite colours of students. If the bar for 'Blue' is tallest and for 'Yellow' is shortest, which statement is true?", "options": {"A": "Blue is least favourite.", "B": "Yellow is most favourite.", "C": "More students like Blue than Yellow.", "D": "Fewer students like Blue."}, "correct_answer": "C"},
    {"id": 30, "difficulty": "medium", "question": "If a bar graph's y-axis starts at 20 instead of 0, what problem can occur?", "options": {"A": "Bars will be too short.", "B": "Differences between bars will look exaggerated.", "C": "Graph will be more accurate.", "D": "No problem."}, "correct_answer": "B"},
    {"id": 31, "difficulty": "medium", "question": "Given a bar graph of test scores out of 50 for 4 students: Ravi=40, Priya=35, Sam=45, Tina=30. What is the median score?", "options": {"A": "35", "B": "37.5", "C": "40", "D": "42.5"}, "correct_answer": "B"},
    {"id": 32, "difficulty": "medium", "question": "A double bar graph shows Maths and Science scores for 4 students. How can you find who improved the most from Maths to Science?", "options": {"A": "Find student with highest Science bar.", "B": "Find student with largest difference between two bars.", "C": "Find student with lowest Maths bar.", "D": "Cannot be found from graph."}, "correct_answer": "B"},
    {"id": 33, "difficulty": "medium", "question": "The scale of a bar graph is 1 cm = 100 km. How long will the bar be for a distance of 450 km?", "options": {"A": "4 cm", "B": "4.5 cm", "C": "5 cm", "D": "5.5 cm"}, "correct_answer": "B"},
    {"id": 34, "difficulty": "medium", "question": "In a survey of 60 people, 15 prefer Tea. In a bar graph with total bar height for all 60 as 12 cm, how high should the Tea bar be?", "options": {"A": "2 cm", "B": "3 cm", "C": "4 cm", "D": "5 cm"}, "correct_answer": "B"},
    {"id": 35, "difficulty": "medium", "question": "A bar graph shows monthly rainfall. The bar for July is missing. If the total rainfall for the year is 120 cm and the sum of bars for other months is 110 cm, July's rainfall is?", "options": {"A": "5 cm", "B": "10 cm", "C": "12 cm", "D": "15 cm"}, "correct_answer": "B"},
    {"id": 36, "difficulty": "medium", "question": "If the range of data in a bar graph is 45 and the smallest value is 15, what is the largest value?", "options": {"A": "30", "B": "45", "C": "60", "D": "75"}, "correct_answer": "C"},
    {"id": 37, "difficulty": "medium", "question": "Which is NOT an essential part of a bar graph?", "options": {"A": "Title", "B": "Labeled axes", "C": "Scale", "D": "Color of bars"}, "correct_answer": "D"},
    {"id": 38, "difficulty": "medium", "question": "In a horizontal bar graph, the quantity is shown on the ___.", "options": {"A": "left axis", "B": "x-axis", "C": "y-axis", "D": "top axis"}, "correct_answer": "B"},
    {"id": 39, "difficulty": "medium", "question": "To show the percentage contribution of each category, which graph is better than a bar graph?", "options": {"A": "Line graph", "B": "Pie chart", "C": "Double bar graph", "D": "Histogram"}, "correct_answer": "B"},
    {"id": 40, "difficulty": "medium", "question": "A bar graph has bars of equal width. If the width of each bar is 1.5 cm and the gap between bars is 0.5 cm, what is the distance from the start of first bar to the end of the third bar?", "options": {"A": "4.5 cm", "B": "5.5 cm", "C": "6.5 cm", "D": "7.5 cm"}, "correct_answer": "C"},
    {"id": 41, "difficulty": "medium", "question": "In a class of 40, a bar graph shows 10 students like cricket. What fraction of students like cricket?", "options": {"A": "1/8", "B": "1/4", "C": "1/3", "D": "1/2"}, "correct_answer": "B"},
    {"id": 42, "difficulty": "medium", "question": "The y-axis of a bar graph has marks: 0, 10, 20, 30... What is the scale?", "options": {"A": "1 unit = 1 mark", "B": "1 unit = 5 marks", "C": "1 unit = 10 marks", "D": "Cannot be determined"}, "correct_answer": "C"},
    {"id": 43, "difficulty": "medium", "question": "For the data: A=50, B=70, C=30, D=90, if the bar for D is 9 cm high, what is the scale (1 cm = ?)", "options": {"A": "5", "B": "10", "C": "15", "D": "20"}, "correct_answer": "B"},
    {"id": 44, "difficulty": "medium", "question": "Which bar graph would have bars of decreasing height?", "options": {"A": "Marks of students in ascending roll order", "B": "Cities sorted by population descending", "C": "Days of the week", "D": "Random data"}, "correct_answer": "B"},
    {"id": 45, "difficulty": "medium", "question": "If a bar graph's highest bar is 8.2 cm and represents 164 items, what does 1 cm represent?", "options": {"A": "10 items", "B": "15 items", "C": "20 items", "D": "25 items"}, "correct_answer": "C"},
    {"id": 46, "difficulty": "medium", "question": "In a bar graph, if one bar is exactly twice as high as another, what does it indicate?", "options": {"A": "The quantity is double.", "B": "The category is better.", "C": "The scale is double.", "D": "It is a mistake."}, "correct_answer": "A"},
    {"id": 47, "difficulty": "medium", "question": "A survey shows 30% like football, 40% cricket, 20% hockey, 10% tennis. Which bar will be second tallest?", "options": {"A": "Football", "B": "Cricket", "C": "Hockey", "D": "Tennis"}, "correct_answer": "A"},
    {"id": 48, "difficulty": "medium", "question": "To compare the population of India, China, USA, and Brazil over the last two decades, the best graph is ___.", "options": {"A": "Simple bar graph for one year", "B": "Multiple bar graph for each year", "C": "Pie chart for one year", "D": "Line graph for each country"}, "correct_answer": "D"},
    {"id": 49, "difficulty": "medium", "question": "The mean of the values represented by bars of heights 5, 10, 15, 20 units (scale: 1 unit = 2) is?", "options": {"A": "12.5 units", "B": "25", "C": "50", "D": "12.5 actual value"}, "correct_answer": "B"},
    {"id": 50, "difficulty": "medium", "question": "If a bar graph shows the number of cars sold each month, which month had sales 25% less than the highest sale month?", "options": {"A": "Can be found by comparing bar heights", "B": "Cannot be found without exact numbers", "C": "Only if total is given", "D": "Only if average is known"}, "correct_answer": "A"},
    {"id": 51, "difficulty": "medium", "question": "A bar graph has no title. What is the biggest problem?", "options": {"A": "Bars might be ugly.", "B": "We won't know what data the graph represents.", "C": "Scale might be wrong.", "D": "Axes might be unlabeled."}, "correct_answer": "B"},
    {"id": 52, "difficulty": "medium", "question": "Which of these can be a disadvantage of a bar graph compared to a table?", "options": {"A": "It is visual.", "B": "It is hard to read exact values.", "C": "It compares categories easily.", "D": "It shows patterns."}, "correct_answer": "B"},
    {"id": 53, "difficulty": "medium", "question": "The total of all bar heights in a graph is 150 cm. If the scale is 1 cm = 3 people, how many people were surveyed in total?", "options": {"A": "150", "B": "300", "C": "450", "D": "600"}, "correct_answer": "C"},
    {"id": 54, "difficulty": "medium", "question": "If the bars in a graph are arranged in descending order of height, the graph is called a ___", "options": {"A": "Histogram", "B": "Pareto chart", "C": "Pictograph", "D": "Line graph"}, "correct_answer": "B"},
    {"id": 55, "difficulty": "medium", "question": "In a double bar graph, the two bars for each category are usually ___.", "options": {"A": "of same color", "B": "side by side", "C": "stacked", "D": "far apart"}, "correct_answer": "B"},
    {"id": 56, "difficulty": "medium", "question": "A bar graph shows the number of hours students study. If the bar for 'Rohan' is 4.5 cm and scale is 1 cm = 2 hours, how many hours does Rohan study?", "options": {"A": "4.5", "B": "6.5", "C": "9", "D": "10"}, "correct_answer": "C"},
    {"id": 57, "difficulty": "medium", "question": "To show the frequency of different height ranges of students, which graph is used?", "options": {"A": "Bar graph", "B": "Histogram", "C": "Pie chart", "D": "Line graph"}, "correct_answer": "B"},
    {"id": 58, "difficulty": "medium", "question": "The difference between the bar heights for 'Winter' and 'Summer' in a rainfall graph is 3 cm. If scale is 1 cm = 20 mm, what is the actual difference in rainfall?", "options": {"A": "3 mm", "B": "20 mm", "C": "60 mm", "D": "80 mm"}, "correct_answer": "C"},
    {"id": 59, "difficulty": "medium", "question": "If a bar graph is drawn with bars of different widths, what is the consequence?", "options": {"A": "It is more attractive.", "B": "It can mislead the viewer.", "C": "It is more accurate.", "D": "It is a standard practice."}, "correct_answer": "B"},
    {"id": 60, "difficulty": "medium", "question": "Given a bar graph with categories representing age groups: 0-10, 10-20, etc., this is actually a ___.", "options": {"A": "Histogram", "B": "Pie chart", "C": "Line graph", "D": "Double bar graph"}, "correct_answer": "A"},
    {"id": 61, "difficulty": "medium", "question": "If the scale of a graph is changed from 1 cm = 10 units to 1 cm = 20 units, what happens to the bar heights?", "options": {"A": "They double.", "B": "They halve.", "C": "They remain same.", "D": "They become four times."}, "correct_answer": "B"},
    {"id": 62, "difficulty": "medium", "question": "In a stacked bar graph, each bar is divided into segments. What does the total height of a bar represent?", "options": {"A": "The largest segment", "B": "The sum of all segments for that category", "C": "The average of segments", "D": "The difference between segments"}, "correct_answer": "B"},
    {"id": 63, "difficulty": "medium", "question": "A bar graph shows the favorite subject of students. If the bar for Maths is 30% taller than the bar for English, and English has 20 students, how many like Maths?", "options": {"A": "23", "B": "26", "C": "30", "D": "33"}, "correct_answer": "B"},
    {"id": 64, "difficulty": "medium", "question": "The bars for 'Cat' and 'Dog' in a pet survey graph have heights 8 cm and 12 cm. What is the ratio of people who prefer cats to dogs?", "options": {"A": "2:3", "B": "3:2", "C": "4:3", "D": "3:4"}, "correct_answer": "A"},
    {"id": 65, "difficulty": "medium", "question": "To show the progress of a student's test scores over 5 tests, a ___ might be better than a bar graph.", "options": {"A": "Pie chart", "B": "Line graph", "C": "Histogram", "D": "Pictograph"}, "correct_answer": "B"},
    {"id": 66, "difficulty": "medium", "question": "What is the total number of students if the bar graph shows 5 bars with heights (in cm) 4, 5, 6, 7, 8 and scale is 1 cm = 4 students?", "options": {"A": "30", "B": "120", "C": "150", "D": "180"}, "correct_answer": "B"},
    {"id": 67, "difficulty": "medium", "question": "If the mode of a data set is the category with the tallest bar, what is the mode for a bar graph with bar heights 7, 9, 9, 5, 6?", "options": {"A": "The first category", "B": "The second category", "C": "The third category", "D": "Both second and third"}, "correct_answer": "D"},
    {"id": 68, "difficulty": "medium", "question": "A bar graph is drawn on a grid. Each small square represents 2 units. If a bar covers 7 full squares and half of another, what value does it represent?", "options": {"A": "7 units", "B": "14 units", "C": "15 units", "D": "16 units"}, "correct_answer": "C"},
    {"id": 69, "difficulty": "medium", "question": "The y-axis of a bar graph is labeled 'Frequency'. What does this mean?", "options": {"A": "How often the graph is used", "B": "The number of items in each category", "C": "The speed of data collection", "D": "The time interval"}, "correct_answer": "B"},
    {"id": 70, "difficulty": "medium", "question": "A bar graph compares the GDP of 5 countries. Which country has the highest GDP?", "options": {"A": "The one with the widest bar", "B": "The one with the tallest bar", "C": "The one with the darkest color", "D": "The first one on the axis"}, "correct_answer": "B"},
    {"id": 71, "difficulty": "medium", "question": "If a bar graph is redrawn with the scale halved, what happens to the visual impression?", "options": {"A": "Bars look taller.", "B": "Bars look shorter.", "C": "No change.", "D": "Graph becomes smaller."}, "correct_answer": "A"},
    {"id": 72, "difficulty": "medium", "question": "In a bar graph showing monthly expenses, if the bar for March is missing but the average expense for the year is known, can we find March's expense?", "options": {"A": "Yes, always", "B": "No, never", "C": "Only if other months' values are known", "D": "Only if total is known"}, "correct_answer": "C"},
    {"id": 73, "difficulty": "medium", "question": "Which type of data is NOT suitable for a bar graph?", "options": {"A": "Categorical data", "B": "Discrete data", "C": "Continuous data over time", "D": "Data with too many categories (e.g., 50)"}, "correct_answer": "D"},
    {"id": 74, "difficulty": "medium", "question": "What is the advantage of a horizontal bar graph over a vertical one?", "options": {"A": "Easier to write category names", "B": "Takes less space", "C": "More accurate", "D": "Bars are always taller"}, "correct_answer": "A"},
    {"id": 75, "difficulty": "medium", "question": "A bar graph's y-axis has marks at 0, 5, 10, 15... The bar for 'P' ends halfway between 10 and 15. What is its value?", "options": {"A": "10", "B": "12.5", "C": "13", "D": "15"}, "correct_answer": "B"},
    {"id": 76, "difficulty": "medium", "question": "If the total of all bar values is 200 and there are 5 bars, what is the average bar height in actual values (not cm)?", "options": {"A": "20", "B": "40", "C": "50", "D": "200"}, "correct_answer": "B"},
    {"id": 77, "difficulty": "medium", "question": "A bar graph shows the number of visitors to a park each day. Which day had 20% fewer visitors than the busiest day?", "options": {"A": "Can be found by comparing bar heights", "B": "Cannot be found without numbers", "C": "Only if total visitors is known", "D": "Only if scale is 1:1"}, "correct_answer": "A"},
    {"id": 78, "difficulty": "medium", "question": "When drawing a bar graph, what should you do first?", "options": {"A": "Draw the bars", "B": "Choose colors", "C": "Decide the scale and draw axes", "D": "Write the title"}, "correct_answer": "C"},
    {"id": 79, "difficulty": "medium", "question": "If a bar graph is used to show the distribution of marks (0-10, 10-20, etc.), it is called a ___.", "options": {"A": "Frequency polygon", "B": "Histogram", "C": "Ogive", "D": "Pictograph"}, "correct_answer": "B"},
    {"id": 80, "difficulty": "medium", "question": "A bar graph has a bar of height 0. What does this mean?", "options": {"A": "Data is missing.", "B": "The frequency for that category is zero.", "C": "Scale is wrong.", "D": "It is the smallest category."}, "correct_answer": "B"},

    {"id": 81, "difficulty": "hard", "question": "A bar graph shows sales for 6 months. The sales in July are 25% more than the average sales of the first 5 months. Can July's sales be determined from the graph alone?", "options": {"A": "Yes, always", "B": "No, more information needed", "C": "Only if total annual sales is known", "D": "Only if scale is 1:1"}, "correct_answer": "B"},
    {"id": 82, "difficulty": "hard", "question": "In a bar graph, the ratio of the heights of bars for A and B is 3:5. If the actual value for B is 250, what is the value for A, assuming uniform scale?", "options": {"A": "150", "B": "200", "C": "300", "D": "350"}, "correct_answer": "A"},
    {"id": 83, "difficulty": "hard", "question": "A survey result is shown in a bar graph and a pie chart. The bar graph has a bar of height 6 cm for 'Yes' and 4 cm for 'No'. If the pie chart's total angle is 360°, what is the angle for 'Yes'?", "options": {"A": "144°", "B": "180°", "C": "216°", "D": "240°"}, "correct_answer": "C"},
    {"id": 84, "difficulty": "hard", "question": "A company's profit over 5 years is shown in a bar graph. The profits are in lakhs: 20, 25, 30, 35, 40. If the bar for the first year is 4 cm high, what is the height of the bar for the last year?", "options": {"A": "6 cm", "B": "7 cm", "C": "8 cm", "D": "9 cm"}, "correct_answer": "C"},
    {"id": 85, "difficulty": "hard", "question": "The bars in a graph represent the number of students in classes I to V. The total number of students is 200. The bar heights are in the ratio 2:3:4:5:6. How many students are in Class IV?", "options": {"A": "30", "B": "40", "C": "50", "D": "60"}, "correct_answer": "C"},
    {"id": 86, "difficulty": "hard", "question": "A double bar graph compares the scores of two teams in 5 games. Team A's bars: 50, 60, 70, 80, 90. Team B's bars: 40, 50, 60, 70, 80. What is the mean difference in scores per game?", "options": {"A": "5", "B": "10", "C": "15", "D": "20"}, "correct_answer": "B"},
    {"id": 87, "difficulty": "hard", "question": "In a bar graph, the bar for category X is 20% shorter than the bar for category Y. If the actual value for Y is 500, what is the value for X?", "options": {"A": "400", "B": "450", "C": "480", "D": "520"}, "correct_answer": "A"},
    {"id": 88, "difficulty": "hard", "question": "A bar graph uses a scale where 1 cm = k units. The bar heights are 2 cm, 5 cm, 7 cm. The actual values are 10, 25, 35. What is k?", "options": {"A": "2", "B": "5", "C": "7", "D": "10"}, "correct_answer": "B"},
    {"id": 89, "difficulty": "hard", "question": "The range of the data in a bar graph is 80. If the smallest bar is 3 cm high and represents 60, and the largest bar is 11 cm high, what is the scale (1 cm = ?)", "options": {"A": "10", "B": "12", "C": "15", "D": "20"}, "correct_answer": "D"},
    {"id": 90, "difficulty": "hard", "question": "A bar graph has 6 bars. The average height of the bars is 8 cm. The first five bars have heights 5, 7, 9, 10, 11 cm. What is the height of the sixth bar?", "options": {"A": "4 cm", "B": "5 cm", "C": "6 cm", "D": "7 cm"}, "correct_answer": "C"},
    {"id": 91, "difficulty": "hard", "question": "In a bar graph showing population density of 5 countries, the bars are in the ratio 1:2:3:4:5. If the smallest density is 50 people/km², what is the largest density?", "options": {"A": "100", "B": "150", "C": "200", "D": "250"}, "correct_answer": "D"},
    {"id": 92, "difficulty": "hard", "question": "A student draws a bar graph with bars touching each other. The data represents the number of cars passing by each hour. What kind of data is this?", "options": {"A": "Discrete categorical", "B": "Continuous", "C": "Ordinal", "D": "Nominal"}, "correct_answer": "B"},
    {"id": 93, "difficulty": "hard", "question": "The heights of bars in a graph are proportional to the square roots of the actual values. If a bar is 4 cm high for an actual value of 64, what is the height for an actual value of 144?", "options": {"A": "5 cm", "B": "6 cm", "C": "7 cm", "D": "8 cm"}, "correct_answer": "B"},
    {"id": 94, "difficulty": "hard", "question": "A bar graph is misleading because the y-axis starts at 100. If the bars show values 120, 130, 140, the visual difference between bars appears larger than the actual difference by what factor?", "options": {"A": "2 times", "B": "3 times", "C": "5 times", "D": "10 times"}, "correct_answer": "B"},
    {"id": 95, "difficulty": "hard", "question": "In a bar graph, the total frequency is 240. The angles for the corresponding pie chart for the first two categories are 60° and 90°. What is the frequency of the third category?", "options": {"A": "60", "B": "70", "C": "80", "D": "90"}, "correct_answer": "C"},
    {"id": 96, "difficulty": "hard", "question": "A bar graph shows the percentage of votes for 4 parties. The bars are 3 cm, 4.5 cm, 6 cm, 7.5 cm. If the total votes are 20000, how many votes did the party with the 6 cm bar get?", "options": {"A": "4000", "B": "5000", "C": "6000", "D": "8000"}, "correct_answer": "C"},
    {"id": 97, "difficulty": "hard", "question": "For a set of data, the bar graph and pie chart are drawn. The bar for 'Apples' is 20% taller than the bar for 'Oranges'. What is the ratio of the angles for Apples and Oranges in the pie chart?", "options": {"A": "5:6", "B": "6:5", "C": "4:5", "D": "5:4"}, "correct_answer": "B"},
    {"id": 98, "difficulty": "hard", "question": "A bar graph's scale is 1 unit = 25 items. The bar for category M is 3.2 units high. How many items does it represent?", "options": {"A": "70", "B": "75", "C": "80", "D": "85"}, "correct_answer": "C"},
    {"id": 99, "difficulty": "hard", "question": "In a bar graph comparing test scores before and after tuition (double bar graph), if for student X the improvement is shown by an increase of 4 cm in bar height and scale is 1 cm = 5 marks, what is the mark improvement?", "options": {"A": "10", "B": "15", "C": "20", "D": "25"}, "correct_answer": "C"},
    {"id": 100, "difficulty": "hard", "question": "The mean of the data represented by a bar graph is 45. The bar heights are 2, 4, 6, 8, x cm with a scale of 1 cm = 10 units. What is x?", "options": {"A": "5", "B": "6", "C": "7", "D": "8"}, "correct_answer": "A"}
  ]
}