Question 1071715

Cameron has 45 coins, all dimes and quarters. The total value of the coins is $9.15.
  How many dimes?
  How many Quarters?
 Thank you!
<pre>Let number of dimes be D
Then number of quarters is: 45 - D
We then get the following VALUE equation: .1D + .25(45 - D) = 9.15
.1D + 11.25 - .25D = 9.15
.1D - .25D = 9.15 - 11.25
- .15D = - 2.1
D, or number of dimes = {{{highlight_green(matrix(1,3, (- 2.1)/(- .15), "=", 14))}}}
Number of quarters: {{{highlight_green(matrix(1,3, 45 - 14, "=", 31))}}}