Simple interest on a certain sum of money at the rate of 5% per annum for 4…
2022
Simple interest on a certain sum of money at the rate of 5% per annum for 4 years is Rs. 800. What will be the compound interest on the same sum for the same period and at the same rate of interest, rounded to the nearest rupee?
Answer: D. 862 — ConceptSimple interest is calculated on the original principal: SI = P×r×t/100. Compound interest is calculated on the growing balance: A = P(1 + r/100)t and…
- A.
850
- B.
840
- C.
855
- D.
862
Attempted by 3 students.
Show answer & explanation
Correct answer: D
Concept
Simple interest is calculated on the original principal: SI = P×r×t/100. Compound interest is calculated on the growing balance: A = P(1 + r/100)t and CI = A − P.
Application
From 800 = P×5×4/100, the principal is P = 4,000.
The compound amount is A = 4,000(1.05)4 = 4,862.025.
Therefore, CI = 4,862.025 − 4,000 = 862.025, which is Rs. 862 to the nearest rupee.
Cross-check
The yearly interest amounts are 200, 210, 220.50, and 231.525; their sum is 862.025.
Result: Rs. 862.