SOLUTION: How do I work this problem? Suppose you just have just enough dimes and quarters to pay for a loaf of bread and quart of milk, which cost $3.45. You have a total of 15 dimes and q

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Question 101076: How do I work this problem?
Suppose you just have just enough dimes and quarters to pay for a loaf of bread and quart of milk, which cost $3.45. You have a total of 15 dimes and quarters.
Let d = the number of dimes you have.
Let q = the number of quarters you have.
a. Write a system of equations that models the information given above.
b. Solve the system for the number of dimes and quarters you have. You may want to solve this by graphing.

Found 2 solutions by edjones, stanbon:
Answer by edjones(8007) (Show Source):
You can put this solution on YOUR website!
q+d=15
.25q+.1d=3.45
the graph says 13 quarters and 2 dimes.
sounds good to me.
Ed

Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
Suppose you just have just enough dimes and quarters to pay for a loaf of bread and quart of milk, which cost $3.45. You have a total of 15 dimes and quarters.
Let d = the number of dimes you have.
Let q = the number of quarters you have.
a. Write a system of equations that models the information given above.
Quantity EQUATION: d+q = 15
Value EQUATION: 10d + 35q = 345 cents
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b. Solve the system for the number of dimes and quarters you have. You may want to solve this by graphing.
It's easier to solve by elimination:
10d + 10q = 150
10d + 35q = 345
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Substract to get:25q = 195
q = 7.8
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Comment:
q should be a whole number. Check your posting
to see if you have it correct.
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Cheers,
Stan H.