Question 592183
Diane has $1.80 in dimes and nickels. She has a total of 22 coins. How many of each kind does she have? 
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Equations:
Quantity: d + n = 22 coins
Value:  10d +5n = 180
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Multiply thru the Quantity Eq. by 5 to get:
5d + 5n = 110
10d + 5n = 180
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Subtract and solve for "d":
5d = 70
d = 14 (# of dimes)
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Solve for "n":
d + n = 22
14 + n = 22
n = 8 (# of nickels)
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Cheers,
Stan H.
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