A piggy bank has nickles and dimes totaling $1.15. If the bank contains exactly 15 coins, how many of each coin are in the bank?
+128407 Call the nuber of nickles x
So....the number of dimes = 15 - x
So
Number of Nickels * Value Each + Number of Dimes * Value Each = Total Value
x * 5 + (15 - x) * 10 = 115 simplify
5x + 150 - 10x = 115 subtract 150 from both sides
-5x = -35 divide both sides by -5
x = 7 = number of nickels
15 - 7 = 8 = number of dimes
