<PRE><B>Question 232569</B>
you have total of 50 coins in your pocket.you only quarters and dimes and the total value $ is 11.00
 how many of each coin do you have 

You have the equations mixed up
:
Total coin equation
q + d = 50
or
d = (50-q); use this for substitution
:
and 
total value equation
.25q + .10d = 11.00
:
Substitute (50-q) for d, find q
.25q + .10(50-q) = 11
:
.25q + 5 - .10q = 11
:
.25q - .10d = 11 - 5
;
.15q = 6
q = {{{6/.15}}}
q = 40 quarters
then
50 - 40 = 10 dimes
:
:
Check solution in the total value equation
.25(40) + .10(10) = 
10 + 1 = 11
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