Question

Fred has a bag of coin with only nickels and quarters. He got $20 by

putting it into a machine. He had 100 coins in the bag.
a. Write two equations to represent this situation.

Answer 1

75 quarters 25 nickels

Explanation:

q=quarters n=nickels

q+n=100 n=100-q

0.25q +0.05(100-q)=20

From now I will multiply by 100 to avoid decimals

25q + 5(100-q)=2000

20q=1500

q=75 n=25

75*0.25= 18.75

25*0.05=1.25

18.75+1.25=20