At what rate of simple interest per annum will a sum triple itself in 30 years? [Give your answer correct to 2 decimal places.]

6.67% 4.75% 8.33% 3.33%

6.67%

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%