Question

3. Manjeet pays ** 70 interest in one year. How long will it take him to pay
a. 280
b. 630
c. 1,470
the rate of interest is​

Answer 1

Answer:

a. 4 years

b. 9 years

c. 21 years

Step-by-step explanation:

Let's assume the Principal = P,

Interest rate = R% per annum

Period in number of years = T

∴ Interest Amount, I = $\frac{PRT}{100}$

Now Manjeet pays 70 interest in one year:

70 = $\frac{PR}{100}$

∴ PR = 7000.

a. 280 = $\frac{PRT}{100}$ = 70T

∴ T = $\frac{280}{70}$ = 4 years.

b. 630 = $\frac{PRT}{100}$ = 70T

∴ T = $\frac{630}{70}$ = 9 years.

c. 1,470 = $\frac{PRT}{100}$ = 70T

∴ T = $\frac{1470}{70}$ = 21 years.