The compound interest on a certain sum for 2 years is 40.80 and the S.I. is Rs.40.find the sum?

• ANS : RS 500.00
  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 )
• 11 years agoHelpfull: Yes(10) No(2)
• answer--->500Rs
  1st yr--->> SI:20
  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
• 11 years agoHelpfull: Yes(7) No(2)
• 4% and Sum Rs.500 ...
• 9 years agoHelpfull: Yes(0) No(0)