Question

What rate of interest of CI sum of money become 6 times the original value ​

Answer 1

Using the compound interest formula, the rate of interest at which the sum of money will become 6 times itself in 15 years compounded annually is 12.25%.

`A = P(1 + r/n)^{(nt)`

Where:

The amount of money accumulated after 15 years, including interest = A.

The principal amount (initial sum of money) = P

The annual interest rate (in decimal) = r

The number of times that interest is compounded per year = n

The time the money is invested for in years = t

After 15 years, A = 6P.

Substituting these values into the formula for compound interest:

6P = P(1 + r/1)
`^{(1*15)`

6 = (1 + r)
`^{15`

We take the 15th root of both sides to get:

1 + r = 6
`^{(1/15)`

1 + r = 1.1225

r = 0.1225

0.1225 = 12.25% (0.1225 x 100)

r = 12.25%

Thus, the rate of interest per annum at which the sum of money will become 6 times itself in 15 years compounded annually is 12.25%.

Complete Question:

At what rate of interest of CI (Compound Interest) will a sum of money become 6 times the original value in 15 years compounded annually?