SSC GD 2021 PYQ — Question 66

SSC GD Constable (English) - 26th November 2021 Shift 2 • Quantitative Aptitude • Q66

The amount obtained by investing a sum of Rs. 15,000 at 8% p.a. in a certain time is Rs. 17,496, interest compounded annually. What will be the amount (in Rs.) of the same  sumat 15% for the same time, interest compounded monthly?

Show answer & explanation

Correct answer: B

Explanation

The correct answer is option 2 i.e. 19965

Given:

The amount obtained by investing a sum of Rs. 15,000 at 8% p.a. in a certain time is Rs. 17,496, interest compounded annually

Formula used:

Amount = P(1 + R/100)T        ----- (1)

Compound Interest = Amount - Principle           ----- (2)

Where, P = principle, R = rate and T = time

Calculations:

Let the time be x years

Using equation (1), we get

⇒ 15000(1 + 8/100)x = 17496

⇒ 1.08x = 17496/15000

⇒ 1.08x = 1.1664

⇒ 1.08x = 1.082

⇒ x = 2

When the interest is compounded 8 monthly, x = 24/8 = 3

Similarly, rate = 15 × 8/12 = 10%

Using equation (1), we get

⇒ 15000(1 + 10/100)3

⇒ 15000 × 1.1 × 1.1 × 1.1 = 19965