Question

(10) In how many years a sum becomes 4
times of itself at the rate of 12%p.a.?​

Answer 1

Answer:

let us assume the sum as 100rs

intrest of 12% on 100 is 12rs

4time the sum of 100 is 400

so 12rs intrest for 25years (12×25=300) in simple intest.

100 becomes 400 in 25years at 12%p.a SI.

prrof: A= P+I

SI = 100×25×12÷100

so SI = 300

A= 300+100 = 400

so answer is 25years