Question 974381

<pre>
Let the number of quarters be x
Then the number of nickels, using
ONE PART = TOTAL MINUS OTHER PART,
is 55-x.
                      Value      Value
Type       Number       of         of
 of          of        EACH       ALL
coin        coins      coin      coins
-------------------------------------------
quarters      x        $0.25    $0.25x
nickels     55-x       $0.05    $0.05(55-x)
-------------------------------------------
TOTALS      55      -----      $10.15

 The equation comes from the column on the right

  {{{(matrix(4,1,Value,of,ALL,quarters))}}}{{{"+"}}}{{{(matrix(4,1,Value,of,ALL,nickels))}}}{{{"="}}}{{{(matrix(5,1,Total,value,of,ALL,coins))}}}

0.25x + 0.05(55-x) = 10.15

Get rid of decimals by multiplying every term by 100:

     25x + 5(55-x) = 1015

    25x + 275 - 5x = 1015

        20x + 275 = 1015

              20x = 740

                 x = 37 = the number of quarters.

The number of nickels is 55-x or 55-37 or 18 nickels.

Checking:  37 quarters is $9.25 and 18 nickels is $0.90
            That's 55 coins.
            And indeed $9.25 + $0.90 = $10.15
Edwin</pre>