lent this sum to alka at the same rate for two years coterest but paid Rs100 as simple interest.Find the sum and rate of interest.

Question

Find this answer please......

Answer 1

The formula for simple interest is  I = PRT  

 

You have given I = 100 and T = 2 so  

 

100 = PR(2)

50 = PR

 

but this still leaves 2 unknowns (Principal sum and Rate of interest) in a single equation so any combination of P and R such that R = 50/P will work.  For example  

 

P = 5000 and R = 0.01

P = 2500 and R = 0.02

P = 1000 and R = 0.05

P =  500  and R = 0.10 

 

are 4 such solutions.  There are infinitely many more.