SSC MTS 2023 PYQ — Question 11

The correct answer is option 4 i.e. Rs. 40000.

Let the principal = P

Rate of interest R = 30% per annum

Time T = 2 years

Difference between Compound Interest and Simple Interest = Rs. 3600

⇒ SI = $\frac{P × R × T}{100}$

⇒ SI = $\frac{P × 30 × 2}{100}$ = 0.6 P

The Compound Interest (CI) for 2 years = P$(1 + \frac{R}{100})^T - P$

⇒ CI = P$(1 + \frac{30}{100})^T - P$ = P(1.3)² − P

⇒ CI = P × 1.69 − P = 1.69P − P = 0.69P

The Difference Between CI and SI = 0.69P − 0.6P = 3600

⇒ 0.09P = 3600

⇒ P = 3600/0.09 = 40000