Emily had 3 times the number of quarters (25 cents) in his bag than dimes (10 cents).

Question

a. If he had a total of 76 coins, how many of them were quarters?

b. What was the total dollar value of these coins?

Answer 1

Q=3D

Q-3D = 0

Q+D =76

subtract 2nd equation from the 3rd to eliminate one variable:

4D = 76

D = 76/4 = 19 dimes

Q= 76-19 = 57 quarters

57 =3 x 19

19+57 =76

total value = .25(57) + .10(19) = $14.25 + $1.90 = $16.15