Katie has a collection of nickels, dimes and quarters with a total value of $3.80. There are eight more dimes than nickels and four more quarters than nickels, how many of each coin does she have?

Answer 1

n(.05) + d(.10) + q(.25) = 3.80

multiply by 100

5n +10d +25q = 380

divide by 5

n +2d +5q = 76

substitute

d = 8+ n

q= 4+n

n+2(8+n) + 5(4+n) = 76

n+2n+5n = 76 - 16-20

8n = 40

n=40/8 =5

n = 5 nickels

d = 13 dimes

q = 9 quarters

5(.05) + 13(.1) + 9(.25)

= .25 +1.3 +2.25

= 3.8

how many n, d and q meaning n=nickels, d=dimes, q= quarters