Question

A jar contains 46 quarters and pennies. The total value of the coins is $4.30. Which system of equations can be used to find p, the number of pennies, and q, the number of quarters?

Answer 1

16 quarters

30 pennies

Explanation:

q= quarters

p=pennies

set up a system of equations. One equation is for total value, the other is total # of coins.

q + p = 46

0.25q + 0.01p = 4.30 -> multiply this equation by 4 so you can subtract from the top equation

q + P =46

1q + 0.04p = 17.20

subtract the bottom equation from the top

0.96p = 28.8

divide by 0.96

p=30

substitute p in the top equation

q + 30 = 46

subtract 30 from both sides

q = 16