SSC GD 2019 PYQ — Question 71

SSC GD Constable (English) - 18 Feb 2019 Shift 2 • Quantitative Aptitude • Q71

The difference between the simple interest and compound interest (interest is compounded half yearly) on a sum at the rate of 25% per annum for one year is Rs. 4375. What will be the principal?

Show answer & explanation

Correct answer: A

Explanation

The correct answer is option 1 i.e. Rs. 280000.

Understanding/Application

Let principal be 100x

Rate = r = 25%

time = t = 1 year

Simple interest = Prt/100 = (100x × 25 × 1)/100 = 25x

Compound Interest (compounded half yearly for 1 year) = P[(1 + r/200)2 - 1]

= 100x[(1 + 25/200)2 - 1]

= 100x[(9/8)2 - 1]

= 100x × (17/64)

= Rs. 26.5625x

Difference = 26.5625x - 25x = 4375

x = 4375/1.5625

x = 2800

Principal = 100x = 100(2800) = Rs. 280000