Question

If the interest on rs.1200 be more than the interest on rs.1000 by rs.30 in 3 years.Find the rate%

Answer 1

Solution :

Let, r% be the rate of interest per annum.

In 3 years, the interest on Rs. 1200 at r% p.a. be

= Rs. (1200 * 3 * r)/100

= Rs. 36r

and for Rs. 1000, it will be

= Rs. (1000 * 3 * r)/100

= Rs. 30r

By the given condition,

36r - 30r = 30

⇒ 6r = 30

⇒ r = 5

∴ the rate of interest is 5% (Ans.)