A sum of money invested at compound interest doubles itself in 18 years. In how many years will it become 4 times of itself? MCQ with Answer and Explanation

Question

A sum of money invested at compound interest doubles itself in 18 years. In how many years will it become 4 times of itself?

A. 36 years

B. 45 years

C. 54 years

D. 27 years

Answer: Option A

Solution (By JKSSB Mock Tests)

The sum doubles (2^1) in 18 years. It will become 4 (2^2) times in 2 * 18 = 36 years.

This question belongs to: Maths Compound Interest

Request complete Subject PDF

Discuss this Question (0)

No comments yet. Be the first to start the discussion!

Practice More Compound Interest Questions

Question #1

Share Report

What is the compound interest on Rs. 10000 for 1 year at 16% per annum, compounded half-yearly?

A. Rs. 1750

B. Rs. 1700

C. Rs. 1664

D. Rs. 1600

View Answer & Solution Discuss

Get Complete Subject PDF for Maths

Correct Answer: Option C

Explanation:
Half-yearly rate = 16/2 = 8%. Time = 2 half-years. Amount = 10000 * (1 + 8/100)^2 = 10000 * 1.1664 = Rs. 11664. Compound Interest = 11664 - 10000 = Rs. 1664.

This question belongs to: Maths Compound Interest

Question #2

Share Report

What will be the amount on Rs. 2400 at 10% per annum compound interest for 2 years?

A. Rs. 2880

B. Rs. 2904

C. Rs. 2800

D. Rs. 3000

View Answer & Solution Discuss

Get Complete Subject PDF for Maths

Correct Answer: Option B

Explanation:
A = 2400 × (1.1)² = 2400 × 1.21 = 2904.

This question belongs to: Maths Compound Interest

Question #3

Share Report

In how many years will Rs. 900 amount to Rs. 1089 at 10% per annum compound interest?

A. 2.5 years

B. 1.5 years

C. 1 year

D. 2 years

View Answer & Solution Discuss

Get Complete Subject PDF for Maths

Correct Answer: Option D

Explanation:
900(1.1)^t = 1089 ⇒ (1.1)^t = 1.21 ⇒ t = 2.

This question belongs to: Maths Compound Interest

Explore All Compound Interest MCQs