A parking meter has nickels and dimes worth 3.50. 45 coins in all. How many of each are there

Question

a parking meter contains nickels and dimes worth 3.50. There are 45 coins in all. Find how many of each there are.

Answer 1

Let n = the number of nickels

Let d = the number of dimes

n + d = 45       d = 45 - n

.05n + .10d = 3.50

.05n + .10(45 - n) = 3.50

.05n + 4.5 - .10n = 3.50

-.05n = -1.00

n = 20 nickels

d = 45 - 20

d = 25 dimes