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Maria has $1.25 in nickels and dimes. She has a total of 16 coins. How many of each coin does he have?

User Rmcsharry
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1 Answer

11 votes
q=quarters, d=dimes


q+d=8
.25q+.1d=1.25

Let's set the first equation to equal d.

d=8-q

.25q+.1(8-q)=1.25

Distribute.

.25q+.8-.1q=1.25

Combine Like Terms

.15q+.8=1.25

Subtract .8

.15q=.45

Divide by .15

q=3

Now, let's solve for d in the first equation.

d+3=8

Subtract 3, and you get d=5

So, there are 5 dimes and 3 quarters in Maribel's pocket.

Check: .25(3)+.1(5)=1.25

.75+.5=1.25
1.25=1.25 which is true.
User TheRyanMark
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