SOLUTION: A contractor mixes concrete from bags of pre-mix for small jobs. How many bags with 3% cement should he mix with 10 bags of 18.2% cement to produce a mix containing 11% cement?
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Question 1025511: A contractor mixes concrete from bags of pre-mix for small jobs. How many bags with 3% cement should he mix with 10 bags of 18.2% cement to produce a mix containing 11% cement? Found 2 solutions by fractalier, josmiceli:Answer by fractalier(6550) (Show Source):
You can put this solution on YOUR website! Call the number of bags of 3% cement, x. Then the setup looks like this:
.03x + .182(10) = .11(10+x)
Now solve for x.
.03x + 1.82 = 1.1 + .11x
.72 = .08x
x = 9 bags of 3% cement
You can put this solution on YOUR website! Let = bags of 3% cement needed bags of pure cement in 18.2% mix
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9 bags of 3% cement are needed
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check:
OK