Question

Mahesh borrowed a certain sum for 2 years at the simple interest from Bhim Mahesh lent this sum to Vishnu at the same rate for 2 years compound interest at the end of 2 years Mahesh received rupees 410 as compound interest but he paid rupees 400 as simple interest find the sum and rate of
interest

Answer 1

400 si for 2 years dat is 200 for each and known si and ci for 1 year are same therefore in year 1 it would have been 200 and known that Ci is interest on interest for second year therefore 200+10 that 10 is interest on 200 interest so
10=what percent of 200 that is 5% so interest rate is 5 and ahead use the formula P*R*N /100=400 our values given:p*5/100*2=400
400*100/5*2=4000