Question

A certain sum is invested for certain time. It amounts
to 500 at 8% pen anum. But when invested at 3% per
anum. It amounts to 200 find the time and sum.​

Answer 1

Answer:

Let the certain sum be S and time be t years

According to question

S+S×10×t=600 .....(1)

S+S×5×t=400 .....(2)

From (1)

S=

(1+10t)

600

.....(3)

From (2)

S(1+5t)=400

(1+10t)

600

(1+5t)=400

Solving we get t=0.2 years