Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Numerical Ability

Topic

Compound Interest

Question:

Ram invested 45% of his salary in a scheme for 3 years which offers 10% per annum compound interest, compounded annually. If he receives ₹5,958 as total interest, then find Ram's salary?

Options:

₹45,000

₹50,000

₹36,000

₹40,000

Correct Answer:

₹40,000

Explanation:

From the formula for compound interest, we know,

C.I = P(1+$\frac{R}{100})^t$– P

5958 = P [ 1 + \(\frac{10}{100}\) ]³ - P

5958 = P [ \(\frac{11}{10}\) × \(\frac{11}{10}\) × \(\frac{11}{10}\) - 1 ]

5958 = P [ \(\frac{1331}{1000}\)  - 1 ]

5958 = P [ \(\frac{331}{1000}\) ]

P = 18000

As, P is equals to 45% of total salary.

So, Total salary = \(\frac{18000}{45}\) × 100

= \(\frac{18000}{9}\) × 20

= Rs. 40000