A sum of money invested at compound interest doubles itself in 4 years. In how many years will it become 16 times itself? MCQ with Answer and Explanation

Explanation:
Difference for 2 years = P * (R/100)^2 => 64 = P * (8/100)^2 => 64 = P * (64 / 10000) => P = Rs. 10000.

Explanation:
D = 8400 × 0.0025 = Rs. 21.

Explanation:
Simple Interest for 1 year = 600 / 2 = Rs. 300. The difference between compound and simple interest is the interest on the first year's interest = 615 - 600 = Rs. 15. Rate of interest = (15 / 300) * 100 = 5%.