Simple Interest [साधारण ब्याज-05

Question: The simple interest on a certain sum of Rs. 160 is Rs. 40, and the number of years is equal to the rate percent per annum. Find the rate percent.  [Ans. (b) 5%]

(a) 5.5%    (b) 5%    (c) 8%   (d) 6%    (e) none of these

Solution:

Detailed Explanation: Rs. 40 is the simple interest of Rs. 160, so SI is ¼ th of the principal, which is 25%. Since the number of years is equal to the rate percent per annum, so (25)^1/2 = 5 is the required numerical value. Therefore, rate is 5% pan or time is 5 years. Ans.