The difference between compound interest received from two difference source on Rs.12500 for 20% is Rs.21600. The difference their years are?
a) 1 year
b) 3 years
c) 5 years
d) 7 years
e) None of these

• Compound interest amount can be calculated using the formula : A = P(1+R/n)^(n*t)
  As per your question,
  R = 0.2
  A1-A2=12500
  P(1-0.2/n)^(n*t1) = P(1-0.2/n)^(n*t2)
  To find : t1-t2
  From above, P on either side can be cancelled out
  i.e. (1-0.2/n)^(n*t1) = (1-0.2/n)^(n*t2)
  Now, the equation can not be simplified further to get solution as there are 2 unknown variables :
  n-number of times the interest is compounded and
  t1-t2 : Difference in their years.
  
  So the question is insufficient.
• 7 years agoHelpfull: Yes(3) No(11)
• as Rs.12500 for 20% is 2500
  so
  we if we add 2500 every year
  after 3 year +
  we get 21600
• 7 years agoHelpfull: Yes(1) No(10)