SOLUTION: Could you please help me with this problem. I am supposed to use a system of equations to solve this question. I have 30 coins worth $6.00. The coins are quarters and dimes. How m

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: Could you please help me with this problem. I am supposed to use a system of equations to solve this question. I have 30 coins worth $6.00. The coins are quarters and dimes. How m      Log On


   



Question 148274: Could you please help me with this problem. I am supposed to use a system of equations to solve this question.
I have 30 coins worth $6.00. The coins are quarters and dimes. How many of each do I have?
Thank you very much!

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
D + Q = 30 (30 Dimes and Quarters)
10D + 25Q = 600 ($6)
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Substitute for D (D=30-Q)
10(30-Q) + 25Q = 600
300 - 10Q + 25Q = 600
15Q = 300
Q = 20
D = 10
Check, it works.