Coin and perimeter word problem

Question

John has eight more quarters than dimes in his piggy bank. If he has total of sixteen dollars, how many of each coin does he have?

Need to write in the let statement. Write an equation, solve and state the answer and need to be sure to include money values with coin problems.

Answer 1

Let Q = # of quarters and D + # dimes

Q = D + 8

and

.25Q + .1D = 16 => 25Q + 10D = 1600 => 5Q + 2D = 320

Substitute

5(D + 8) + 2D = 320

7D + 40 = 320

7D = 280

D = 40

Q = D + 8 = 48