Question

The compound interest on a certain sum for 2 year is rs 40.80 and simple interest is rs. 40 for same year. What will be the ratio of interest.

Answer 1

Answer:

500

Step-by-step explanation:

we know that the SI for every year is same hence SI for 1st yr is 20 and for 2nd year is 20

again for 1st year SI = CI so the difference in CI-SI = 0.8 due to 2nd year

and this difference is due to the interest on the interest of 1st year

so Rate = (0.8/20)*100 = 4%

now we can calculate the sum by formula SI = (p*r*i)/100

p = (20*100)/4 = 500 (we have calculated for 1 year )

CI:20(1st yr CI alwz same as SI)

2nd yr--->> SI:20(same for every year)

CI=20+(20*r*1)/100 note:(1st yr interest)

so 2nd yr CI=2 yr CI-1st yr CI

20+(20*r*1)/100=20.8

r=4%

for 1st yr,p=(100*20)/4*1=500

ratio = 4:1