A sum, when invested at 10% simple interest per annum, amounts to ₹9360 after 3 years. What is the simple interest (in ₹) on the same sum at the same rate in 1 year?

Correct option is C

Given:

Amount (A) after 3 years = ₹9360

Rate of Simple Interest (R) = 10% per annum

Time (T) = 3 years

Formula Used:

Simple Interest (SI) = $$\frac{(P \times R \times T)}{ 100}$$​, where P is the principal.

Amount (A) = P + SI

Solution:

Let the principal be P.

9360 = P + $$\frac{(P \times 10 \times 3)}{ 100}$$​​

9360 = P + 0.3P => 9360 = 1.3P

P = $$\frac{9360 }{1.3 }$$​= ₹7200

SI for 1 year = $$\frac{(7200 \times 10 \times 1)}{ 100}$$​ = ₹720

Therefore, the simple interest on the same sum at the same rate in 1 year is ₹720.