The compound interest for first and second years is 200 and 220 on a certain amount. Find the sum.

• 
  Sum = Rs 2000.
  
  The compound interest for first and second years is 200 and 220 on a certain amount.
  In second year, Rs 20 is simple interest on Rs 200 which is interest for one year on principal sum.
  So rate of interest = 20*100/200 = 10%
  Principal = 200*100/10*1= Rs 2000.
• 12 years agoHelpfull: Yes(33) No(6)
• compound interest is INTEREST on INTEREST.therefore ,we can calculate the rate of interest ,by calculating the rate of interest in the compound interest.
  therefore , Rate of interest = [(220-200)/200]* 100 = 10 %
  let the amount be A, the interest at the rate of 10% is 200 in the first year,
  therefore [A*(10/100)]=200, therefore A = 2000 (ans)
• 12 years agoHelpfull: Yes(15) No(4)
• p((1+r/100)^2-1))=220
  p((1+r/100)^1-1))=200
  solving,these two equatns....
  we get,p=64.5
• 12 years agoHelpfull: Yes(2) No(42)