A certain sum becomes 3 times itself in 4 years at compound interest. In how many years does it become 27 times itself?

Question

A certain sum becomes 3 times itself in 4 years at compound interest. In how many years does it become 27 times itself? (A) 15 years (B) 12 years (C) 36 years (D) 21 years

Tardigrade Admin · Accepted Answer

(i) Use formula for amount. (ii) If 3 P=P(1+(R/100))4, then find R. (iii) If 27 P=P(1+(R/100))n, then find n.

Q. A certain sum becomes 3 times itself in 4 years at compound interest. In how many years does it become 27 times itself?

15 years

12 years

36 years

21 years

(i) Use formula for amount.
(ii) If $3 P = P (1 + \frac{R}{100})^{4}$ , then find $R$ .
(iii) If $27 P = P (1 + \frac{R}{100})^{n}$ , then find $n$ .

Q. A certain sum becomes 3 times itself in 4 years at compound interest. In how many years does it become 27 times itself?

15 years

12 years

36 years

21 years

(i) Use formula for amount. (ii) If 3P=P(1+100R​)4, then find R. (iii) If 27P=P(1+100R​)n, then find n.

(i) Use formula for amount.
(ii) If $3 P = P (1 + \frac{R}{100})^{4}$ , then find $R$ .
(iii) If $27 P = P (1 + \frac{R}{100})^{n}$ , then find $n$ .