Question 314776
A wire 180 centimeters long is to be cut into three pieces. 
a + b + c = 180
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The length of one piece is three times the length of the second. 
a = 3b
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The length of the third piece is 12 centimeters shorter than twice the length of the second.
c = 2b-12
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Find the length of each piece.
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Equation:
Substitute for "a" and for "c":
3b + b + 2b-12 = 180
6b = 192
b = 32
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Since a = 3b, a = 96
Since c = 2b-12, c = 64-12 = 52
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Check:
96 + 32 + 52 = 180
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Cheers,
Stan H.