Question 414848
Fred weighs 187 pounds but is on a diet that makes him lose 1.7 pounds per week. 
F(x) = 187-1.7x
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Barney weighs only 93 pounds but is on a diet that makes him gain 0.9 pounds per week.
B(x) = 93+0.9x
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 What is the number of weeks it takes for Fred and Barney to weigh exactly the same amount?
Solve F(x) = B(x) for "x":
187-1.7x = 93+0.9x
2.6x = 194
x = 74.62
Equal weight during the 74th week,
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 How many weeks does it take for their total weight to equal 252 pounds?
Solve F(x) + B(x) = 252
187-1.7x + 83+0.9x = 252
-0.8x + 270 = 252
-0.8x = -18
x = 22.5 weeks
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Cheers,
Stan H.
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