a total of 324 coins of 20 paise and 25 paise make a sum of  Rs 71, then the number of 25 paise coins is.........
Ans:
Let number of 25 paise coins be x
Then number of 20 paise coins = (324 - x)
Value of the 25 paise coins = (25*x) paise
Value of the 20 paise coins = (20*(324 - x)) paise
Total value = Rs 71 = 7100 paise
So we have the equation
 Solve for x



No. of 25p coins = 124
No. of 20p coins = 324 - 124 = 200
:)