Practice Questions
Concept Explanation
Placement questions often combine simple interest, compound interest, rate changes, and comparisons in a single problem.
Strategy
- Identify whether the problem uses SI or CI.
- Convert time to years (months ÷ 12, days ÷ 365).
- For comparisons, calculate both amounts separately.
- Use difference formulas when CI − SI is asked for 2 or 3 years.
Example
Rs. 10,000 at 10% SI for 2 years gives amount Rs. 12,000. Same at CI annually gives Rs. 12,100.
-
Q1 Easy
Rs. 10,000 at 10% SI for 2 years gives amount:
ExplanationSI = Rs. 2,000. Amount = Rs. 12,000. -
Q2 Easy
Same sum at 10% CI annually for 2 years gives amount:
ExplanationA = 10000 × (1.1)^2 = Rs. 12,100. -
Q3 Medium
At what rate will Rs. 4,000 amount to Rs. 4,480 in 2 years at SI?
ExplanationSI = 480. R = (100×480)/(4000×2) = 6%. -
Q4 Easy
Rs. 5,000 at 12% SI for 5 years. SI is:
ExplanationSI = (5000×12×5)/100 = Rs. 3,000. -
Q5 Medium
Rs. 8,000 at 5% CI annually for 2 years. CI is:
ExplanationA = Rs. 8,820. CI = Rs. 820. -
Q6 Medium
In how many years will Rs. 5,000 double at 10% SI?
ExplanationWhen SI = P, T = 100/R = 10 years. -
Q7 Easy
Rs. 12,000 at 10% for 2 years. CI − SI is:
ExplanationDifference = 12000 × 0.01 = Rs. 120.
-
Q8 Hard
Rs. 6,000 at 20% SI for 1 year and 10% SI for 1 year (total 2 years). Total SI is:
ExplanationYear 1 SI = 1200; Year 2 SI = 600 on same principal. Total = Rs. 1,800. -
Q9 Easy
Rs. 15,000 at 8% SI for 3 years. Amount is:
ExplanationSI = 3600. Amount = Rs. 18,600. -
Q10 Medium
Rs. 10,000 at 5% CI for 2 years minus Rs. 10,000 at 5% SI for 2 years equals:
ExplanationCI amount = 11025; SI amount = 11000. Difference = Rs. 25. -
Q11 Medium
Rs. 20,000 at 10% SI for 3 years. Amount is:
ExplanationSI = 6000. Amount = Rs. 26,000. -
Q12 Medium
Rs. 9,000 at 10% for 2 years CI annually. Amount is:
ExplanationA = 9000 × 1.21 = Rs. 10,890. -
Q13 Easy
Rs. 25,000 at 4% SI for 4 years. SI is:
ExplanationSI = (25000×4×4)/100 = Rs. 4,000. -
Q14 Medium
Rs. 16,000 at 5% for 2 years. CI − SI is:
ExplanationDifference = 16000 × 0.0025 = Rs. 40.
-
DS1 Easy
What is the amount at simple interest?
Statement IP = Rs. 10,000 at 10% for 2 years.
Statement IIInterest type is simple interest.
ExplanationStatement I alone gives amount = Rs. 12,000. -
DS2 Easy
What is the amount at compound interest?
Statement IP = Rs. 10,000 at 10% for 2 years compounded annually.
Statement IITime is 2 years.
ExplanationStatement I alone gives amount = Rs. 12,100.
-
DS3 Medium
What is CI − SI for 2 years?
Statement IP = Rs. 12,000, R = 10%.
Statement IITime is 2 years.
ExplanationTogether: difference = Rs. 120. -
DS4 Hard
Can the sum double in 10 years at 10% SI?
Statement IPrincipal is Rs. 5,000 at 10% simple interest.
Statement IITime is 10 years.
ExplanationTogether: SI = Rs. 5,000 = principal, so the amount doubles.