Ashley has 36 coins totaling $4.20 in quarters and dimes. How many of each coin does she have?
d = dimes value = 10d
q = quarters = 36 -d value = 25 (36-d) the values summed = 420
10d + 25(36-d) = 420 solve for d =# dimes then # q = 36-d
q + d = 36
25q + 10d = 420
q = 36 - d
25 (36 - d) + 10d = 420
900 - 25d + 10d = 420
900 - 15d = 420
15d = 480
d = 32
q + d = 36
q + (32) = 36
q = 4
There are 4 quarters and 32 dimes
Ashley has 36 coins totaling $4.20 in quarters and dimes. How many of each coin does she have?
If all 36 coins were dimes, then Ashley would have 3.60
However, Ashley has 4.20, so we have to raise the total by 0.60
Every time you substitute a quarter for a dime, you gain 0.15
If you substitute four quarters for four dimes, you gain 0.60
So, Ashley has 4 quarters and 32 dimes
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