If a sum of money compound annually amounts of thrice itself in 3 years. In…

20252024

 If a sum of money compound annually amounts of thrice itself in 3 years. In how many years will it become 9 times itself?

  1. A.

    6

  2. B.

    8

  3. C.

    9

  4. D.

    10

Attempted by 18 students.

Show answer & explanation

Correct answer: A

Answer: 6

Explanation:

  1. Let the principal be P. Since the amount triples in 3 years: P*(1+r/100)^3 = 3P, so (1+r/100)^3 = 3 and the annual growth factor is (1+r/100) = 3^(1/3).

  2. For the amount to become 9 times in n years: (1+r/100)^n = 9. Substituting the growth factor gives (3^(1/3))^n = 9, so 3^(n/3) = 3^2.

  3. Compare exponents: n/3 = 2, hence n = 6 years.

Explore the full course: Wipro Preparation