A person invested ₹12,000 on simple interest for 7 years to obtain a total amount of ₹20,400 on a certain annual rate of interest. What was the rate of interest to obtain the above amount?
Answer & explanation
Correct answer: option 4
Principal( P) = 12000 Rs
Rate (R%) = R%
Time ( T ) = 7 years
Amount = 20400 Rs
Interest = Amount - Principal = 20400- 12000 = Rs 8400
⇒ 8400 = \(\frac{12000 ×Rate × 7 }{100}\)
⇒ \(\frac{8400 ×100 }{12000 × 7 }\) = R %
⇒ Rate = 10% p.a