{
  "title": "Growth and Depreciation (Compound Interest) - Grade 9 ICSE",
  "total_questions": 60,
  "questions": [
    {"id": 1, "difficulty": "easy", "question": "What is the formula for compound amount? 💰", "options": {"A": "P + I", "B": "P(1 + r/100)^t", "C": "Prt", "D": "P(1 + rt)"}, "correct_answer": "B"},
    {"id": 2, "difficulty": "easy", "question": "If something grows at 5% per year, r = ?", "options": {"A": "0.5", "B": "5", "C": "0.05", "D": "50"}, "correct_answer": "B"},
    {"id": 3, "difficulty": "easy", "question": "Depreciation means value ______ over time.", "options": {"A": "increases", "B": "decreases", "C": "stays same", "D": "doubles"}, "correct_answer": "B"},
    {"id": 4, "difficulty": "easy", "question": "If population grows, we use ______ formula.", "options": {"A": "simple interest", "B": "compound interest", "C": "addition", "D": "subtraction"}, "correct_answer": "B"},
    {"id": 5, "difficulty": "easy", "question": "A car worth ₹2,00,000 depreciates 10% yearly. After 1 year, value = ? 🚗", "options": {"A": "₹1,80,000", "B": "₹1,90,000", "C": "₹2,20,000", "D": "₹1,70,000"}, "correct_answer": "A"},
    {"id": 6, "difficulty": "easy", "question": "If P = 1000, r = 10, t = 2 years, compound amount = ?", "options": {"A": "1200", "B": "1210", "C": "1100", "D": "1300"}, "correct_answer": "B"},
    {"id": 7, "difficulty": "easy", "question": "Growth percentage is always ______.", "options": {"A": "negative", "B": "positive", "C": "zero", "D": "decimal"}, "correct_answer": "B"},
    {"id": 8, "difficulty": "easy", "question": "Depreciation uses same formula as growth but r is ______.", "options": {"A": "positive", "B": "negative", "C": "zero", "D": "large"}, "correct_answer": "B"},
    {"id": 9, "difficulty": "easy", "question": "Value after depreciation = P(1 - r/100)^t. True or false?", "options": {"A": "True", "B": "False", "C": "Sometimes", "D": "Never"}, "correct_answer": "A"},
    {"id": 10, "difficulty": "easy", "question": "Compound Interest = Amount - ______.", "options": {"A": "Rate", "B": "Principal", "C": "Time", "D": "Interest"}, "correct_answer": "B"},
    {"id": 11, "difficulty": "easy", "question": "If something doubles in 6 years, it is ______ growth.", "options": {"A": "simple", "B": "compound", "C": "linear", "D": "quick"}, "correct_answer": "B"},
    {"id": 12, "difficulty": "easy", "question": "r = 8% growth means multiplying factor per year = ?", "options": {"A": "1.8", "B": "1.08", "C": "0.8", "D": "0.08"}, "correct_answer": "B"},
    {"id": 13, "difficulty": "easy", "question": "A tree grows 3% per year. If height now 5 m, after 1 year = ? 🌳", "options": {"A": "5.3 m", "B": "5.15 m", "C": "5.03 m", "D": "5.5 m"}, "correct_answer": "B"},
    {"id": 14, "difficulty": "easy", "question": "Depreciation of 20% means value becomes ______ of original after 1 year.", "options": {"A": "20%", "B": "80%", "C": "120%", "D": "8%"}, "correct_answer": "B"},
    {"id": 15, "difficulty": "easy", "question": "If P = 500, r = 5%, t = 1 year, compound amount?", "options": {"A": "525", "B": "550", "C": "575", "D": "500"}, "correct_answer": "A"},
    {"id": 16, "difficulty": "easy", "question": "Which term means decrease in value?", "options": {"A": "Appreciation", "B": "Growth", "C": "Depreciation", "D": "Interest"}, "correct_answer": "C"},
    {"id": 17, "difficulty": "easy", "question": "If r = -10%, it means ______.", "options": {"A": "growth", "B": "depreciation", "C": "no change", "D": "profit"}, "correct_answer": "B"},
    {"id": 18, "difficulty": "easy", "question": "P = 800, r = 10% growth, t = 2 years. Find amount.", "options": {"A": "960", "B": "968", "C": "880", "D": "976"}, "correct_answer": "B"},
    {"id": 19, "difficulty": "easy", "question": "Value after 2 years of ₹1000 at 12% growth = ?", "options": {"A": "1240", "B": "1254.4", "C": "1220", "D": "1120"}, "correct_answer": "B"},
    {"id": 20, "difficulty": "easy", "question": "If something loses 15% each year, after 1 year, remains ______%.", "options": {"A": "15", "B": "85", "C": "115", "D": "100"}, "correct_answer": "B"},
    {"id": 21, "difficulty": "medium", "question": "A machine depreciates 8% per year. If new price ₹50,000, value after 1 year? ⚙️", "options": {"A": "₹46,000", "B": "₹48,000", "C": "₹45,000", "D": "₹44,000"}, "correct_answer": "A"},
    {"id": 22, "difficulty": "medium", "question": "Population 10,000 grows 4% per year. Population after 2 years?", "options": {"A": "10,816", "B": "10,800", "C": "10,400", "D": "11,000"}, "correct_answer": "A"},
    {"id": 23, "difficulty": "medium", "question": "A car worth ₹3,00,000 depreciates 12% yearly. Value after 2 years?", "options": {"A": "₹2,64,000", "B": "₹2,32,320", "C": "₹2,40,000", "D": "₹2,50,000"}, "correct_answer": "B"},
    {"id": 24, "difficulty": "medium", "question": "If bacteria double every hour, growth rate % per hour?", "options": {"A": "50%", "B": "100%", "C": "200%", "D": "0%"}, "correct_answer": "B"},
    {"id": 25, "difficulty": "medium", "question": "Principal ₹2000, r = 5%, t = 3 years, compound interest = ?", "options": {"A": "₹315.25", "B": "₹300", "C": "₹331.01", "D": "₹350"}, "correct_answer": "A"},
    {"id": 26, "difficulty": "medium", "question": "A house appreciates 6% per year. Value now ₹25,00,000. Value after 2 years?", "options": {"A": "₹28,09,000", "B": "₹28,00,000", "C": "₹27,50,000", "D": "₹26,50,000"}, "correct_answer": "A"},
    {"id": 27, "difficulty": "medium", "question": "Depreciation formula: V = P(1 - r/100)^t. If P=8000, r=5, t=2, V=?", "options": {"A": "7220", "B": "7600", "C": "7225", "D": "7000"}, "correct_answer": "A"},
    {"id": 28, "difficulty": "medium", "question": "If something grows at 20% per year, multiplying factor = ?", "options": {"A": "0.2", "B": "1.2", "C": "2", "D": "0.8"}, "correct_answer": "B"},
    {"id": 29, "difficulty": "medium", "question": "A tree's height 4m, grows 5% per year. Height after 3 years (approx)?", "options": {"A": "4.6 m", "B": "4.63 m", "C": "5 m", "D": "4.8 m"}, "correct_answer": "B"},
    {"id": 30, "difficulty": "medium", "question": "Value of item after 3 years depreciation at 10% p.a., original ₹10,000?", "options": {"A": "₹7290", "B": "₹7000", "C": "₹8000", "D": "₹9000"}, "correct_answer": "A"},
    {"id": 31, "difficulty": "medium", "question": "Compound growth: A = P(1 + r/100)^t. If P=1200, r=10, t=2, A=?", "options": {"A": "1452", "B": "1440", "C": "1320", "D": "1400"}, "correct_answer": "A"},
    {"id": 32, "difficulty": "medium", "question": "A phone depreciates 15% each year. Price after 2 years if original ₹20,000?", "options": {"A": "₹14,450", "B": "₹15,000", "C": "₹16,000", "D": "₹12,000"}, "correct_answer": "A"},
    {"id": 33, "difficulty": "medium", "question": "Population 5000, grows 3% first year, 4% second year. Population after 2 years?", "options": {"A": "5356", "B": "5400", "C": "5300", "D": "5450"}, "correct_answer": "A"},
    {"id": 34, "difficulty": "medium", "question": "If ₹8000 becomes ₹9261 in 3 years compound interest, rate % = ?", "options": {"A": "4%", "B": "5%", "C": "6%", "D": "7%"}, "correct_answer": "B"},
    {"id": 35, "difficulty": "medium", "question": "A = 1210, P = 1000, t = 2, r = ?", "options": {"A": "10%", "B": "11%", "C": "12%", "D": "9%"}, "correct_answer": "A"},
    {"id": 36, "difficulty": "medium", "question": "Value after 2 years of ₹5000 at 8% depreciation per year?", "options": {"A": "₹4232", "B": "₹4240", "C": "₹4320", "D": "₹4200"}, "correct_answer": "A"},
    {"id": 37, "difficulty": "medium", "question": "If an investment triples in 10 years, annual growth rate % (approx)?", "options": {"A": "10%", "B": "12%", "C": "15%", "D": "20%"}, "correct_answer": "B"},
    {"id": 38, "difficulty": "medium", "question": "Car value after 3 years: ₹2,00,000 at 12% depreciation yearly?", "options": {"A": "₹1,36,294", "B": "₹1,40,000", "C": "₹1,50,000", "D": "₹1,60,000"}, "correct_answer": "A"},
    {"id": 39, "difficulty": "medium", "question": "A town population 24,000 grows 5% per year. After 2 years?", "options": {"A": "26,460", "B": "26,400", "C": "27,000", "D": "25,200"}, "correct_answer": "A"},
    {"id": 40, "difficulty": "medium", "question": "If depreciation rate 10%, value after t years = P × (0.9)^t. True?", "options": {"A": "True", "B": "False", "C": "Depends", "D": "None"}, "correct_answer": "A"},
    {"id": 41, "difficulty": "hard", "question": "A machine depreciates at 10% p.a. After 3 years its value is ₹7290. Original price? 🔧", "options": {"A": "₹10,000", "B": "₹12,000", "C": "₹9,000", "D": "₹8,000"}, "correct_answer": "A"},
    {"id": 42, "difficulty": "hard", "question": "If house value doubles in 8 years, annual growth rate % (approx)?", "options": {"A": "8%", "B": "9%", "C": "10%", "D": "12%"}, "correct_answer": "B"},
    {"id": 43, "difficulty": "hard", "question": "Population grows 2% first year, 3% second year, 4% third year. If initial 50,000, after 3 years?", "options": {"A": "54636", "B": "55000", "C": "56000", "D": "54000"}, "correct_answer": "A"},
    {"id": 44, "difficulty": "hard", "question": "A car bought for ₹5,00,000 depreciates 15% first year, 12% second year. Value after 2 years?", "options": {"A": "₹3,74,000", "B": "₹3,74,400", "C": "₹3,80,000", "D": "₹3,60,000"}, "correct_answer": "A"},
    {"id": 45, "difficulty": "hard", "question": "Compound depreciation: P = 8000, rate = 5% p.a., time = 3 years. Value?", "options": {"A": "₹6859", "B": "₹7000", "C": "₹6500", "D": "₹6800"}, "correct_answer": "A"},
    {"id": 46, "difficulty": "hard", "question": "If ₹10,000 grows to ₹11,025 in 2 years, compound interest rate?", "options": {"A": "4%", "B": "4.5%", "C": "5%", "D": "6%"}, "correct_answer": "C"},
    {"id": 47, "difficulty": "hard", "question": "Value of equipment after 4 years at 8% depreciation, original ₹25,000?", "options": {"A": "₹17,959", "B": "₹18,000", "C": "₹19,000", "D": "₹20,000"}, "correct_answer": "A"},
    {"id": 48, "difficulty": "hard", "question": "A city population grows 3% annually. In how many years will it grow 40% from now? (approx)", "options": {"A": "11 years", "B": "12 years", "C": "13 years", "D": "14 years"}, "correct_answer": "A"},
    {"id": 49, "difficulty": "hard", "question": "A machine depreciates so that after 2 years value is ₹81,000, rate 10% p.a. Find original cost.", "options": {"A": "₹1,00,000", "B": "₹90,000", "C": "₹1,10,000", "D": "₹95,000"}, "correct_answer": "A"},
    {"id": 50, "difficulty": "hard", "question": "Investment grows at 8% first year, 10% second year, 12% third year. If initial ₹20,000, amount after 3 years?", "options": {"A": "₹26,611.20", "B": "₹27,000", "C": "₹26,000", "D": "₹25,500"}, "correct_answer": "A"},
    {"id": 51, "difficulty": "hard", "question": "If an asset loses 20% each year, after how many years will value be less than half? (log approx)", "options": {"A": "3", "B": "4", "C": "2", "D": "5"}, "correct_answer": "A"},
    {"id": 52, "difficulty": "hard", "question": "Bacteria culture grows 25% per hour. Initial 4000, after 3 hours count?", "options": {"A": "7812.5", "B": "8000", "C": "7500", "D": "8200"}, "correct_answer": "A"},
    {"id": 53, "difficulty": "hard", "question": "Depreciation: value after t years V = P(0.9)^t. If V = 6561, P = 10000, t = ?", "options": {"A": "4", "B": "3", "C": "5", "D": "6"}, "correct_answer": "A"},
    {"id": 54, "difficulty": "hard", "question": "House price ₹30,00,000 appreciates 5% first year, depreciates 4% second year. Value after 2 years?", "options": {"A": "₹30,24,000", "B": "₹31,00,000", "C": "₹29,00,000", "D": "₹30,50,000"}, "correct_answer": "A"},
    {"id": 55, "difficulty": "hard", "question": "Car bought for ₹4,00,000, depreciates 8% p.a. Value after 3 years (nearest ₹)?", "options": {"A": "₹3,11,000", "B": "₹3,12,000", "C": "₹3,10,000", "D": "₹3,20,000"}, "correct_answer": "A"},
    {"id": 56, "difficulty": "hard", "question": "If population 1,00,000 grows at 2.5% p.a., after 3 years?", "options": {"A": "1,07,689", "B": "1,07,500", "C": "1,08,000", "D": "1,07,000"}, "correct_answer": "A"},
    {"id": 57, "difficulty": "hard", "question": "Machine worth ₹80,000 depreciates to ₹58,320 in 2 years. Rate of depreciation p.a.?", "options": {"A": "10%", "B": "12%", "C": "15%", "D": "8%"}, "correct_answer": "A"},
    {"id": 58, "difficulty": "hard", "question": "A principal doubles in 6 years at compound interest. In how many years will it quadruple?", "options": {"A": "12 years", "B": "18 years", "C": "24 years", "D": "10 years"}, "correct_answer": "A"},
    {"id": 59, "difficulty": "hard", "question": "Value of ₹15,000 after 4 years at 5% depreciation per year?", "options": {"A": "₹12,202", "B": "₹12,000", "C": "₹11,500", "D": "₹12,500"}, "correct_answer": "A"},
    {"id": 60, "difficulty": "hard", "question": "If ₹P becomes ₹2P in 9 years, compound annual growth rate % (approx)?", "options": {"A": "8%", "B": "9%", "C": "10%", "D": "7%"}, "correct_answer": "A"}
  ]
}