SOLUTION: A soda Machine contains 20 coins. Some of the coins are nickels and the rest are quarters. If the value of the coins is $4.40 find the number of coins of each kind.

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: A soda Machine contains 20 coins. Some of the coins are nickels and the rest are quarters. If the value of the coins is $4.40 find the number of coins of each kind.       Log On


   



Question 268743: A soda Machine contains 20 coins. Some of the coins are nickels and the rest are quarters. If the value of the coins is $4.40 find the number of coins of each kind.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A soda Machine contains 20 coins. Some of the coins are nickels and the rest are quarters. If the value of the coins is $4.40 find the number of coins of each kind.
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2-variable solution:
Equations:
n + q = 20
5n + 25q = 440 cents
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Multiply thru 1st equation by 5 to get:
5n + 5q = 100
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Subtract that from the 2nd equation and solve for "q":
20q = 340
q = 17 (# of quarters)
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Since n+q = 20, n = 3 (# of nickels)
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Cheers,
Stan H.