Casey has $21.40 in dimes and quarters. she had a total of 100 coins. How much of each kind does Casey have?

Answer 1

Hi! We have 100 quarters and dimes that add up to $21.40.

If x = the number of quarters, then 100-x = the number of dimes.

The value of a quarter is 25 cents or $.25, and the value of a time is 10 cents or $.10.

Let’s put this information together.

.25x + .1(100-x) = 21.4

.25x + 10 - .1x = 21.4

.15x + 10 = 21.4

.15x = 21.4 - 10

.15x = 11.4

11.4

x = ------

 .15

x = 76 quarters

100 – x = 24 dimes

76 * .25 = $19.00

24 * .10 = $ 2.40

$19.00 + $2.40 = $21.40!        

Answer 2

19 quarters

24 dimes