At what rate of simple interest per annum will a sum triple itself in 30 years? [Give your answer correct to 2 decimal places.]
Answer & explanation
Correct answer: option 1
Let sum = P
Sum triple itself in 30 years i.e. Amount = 3P
So , Simple interest = 3P - P = 2P
Simple Interest = \(\frac{Principal ×Rate × Time }{100}\)
2P = \(\frac{P × Rate × 30 }{100}\)
2 = \(\frac{ Rate × 30 }{100}\)
Rate = \(\frac{ 100 }{15}\) = 6.67%