Question 1050355: Joan has some dimes and quarters. If she has 30 coins worth a total of $4.95, how many of each type of coin does she have? Found 2 solutions by josmiceli, advanced_Learner:Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! 20 quarters = $5, so too many quarters
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19 quarters = $4.75
2 dimes = $.20
only 21 coins
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18 quarters = $4.50
Can't make $4.95 with dimes
The number of quarters has to be odd
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17 quarters = $4.25
7 dimes = $.70
only 24 coins
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15 quarters = $3.75
12 dimes = $1.20
only 27 coins
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13 quarters = $3.25
17 dimes = $1.70
This is the answer
Solve: We'll use substitution. After moving 1*Q to the right, we get: , or . Substitute that
into another equation: and simplify: So, we know that Q=13. Since , D=17.
