Question 539583: Ray has $7.60 in quarters and dimes. In all, he has 40 coins. How many coins of each kind does he have? Answer by jpg7n16(66) (Show Source):
You can put this solution on YOUR website! Start with what you know. Quarters are worth $0.25 and dimes $0.10 and in total he has $7.60. You add up your number of quarters and dimes, and you get 40. That starts you with 2 equations.
-- or let's make that easier to read --
1) and
2)
The easiest way to solve is to make both equations have the same number of q's or d's. So either make each equation have 25 q's or 10 d's. I'd recommend making both equations have 10 d's, because multiplying is easier with 10. So multiply the 2nd equation by 10.
This leaves you with:
1)
2)
Then take equation 1 minus equation 2 and solve for q.
Now we know there were 24 quarters. Then use the easier equation to figure out how many dimes.
There were 24 quarters and 16 dimes.
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