What will be the difference between simple and compound interest @10% per annum on a sum of tk. 1000 after 4 years?

A Tk. 31

B Tk. 32.10

C Tk. 40.40

D Tk. 64.10

Correct Answer: Option D

at simple interest, tk 1000 after 4 years incurs = 10 x1000x4/100=400 tk at compound interest,

c=p(1+r)n=1000(1+10/100)4=1464.1 tk so, the amount incurred=1464.1-1000=464.1 tk

difference=(464.1-400)tk=64.1 tk