SOLUTION: A cement mixture is composed of 3 elements. By weight, 1/3 of the mixture is sand, 3/5 of the mixture is water, and the remaining 12 pounds of the mixture is gravel. What is the we

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Question 877046: A cement mixture is composed of 3 elements. By weight, 1/3 of the mixture is sand, 3/5 of the mixture is water, and the remaining 12 pounds of the mixture is gravel. What is the weight of the entire mixture in pounds?
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Find 12 pounds is what fraction of the mixture by weight.

1%2F3%2B3%2F5%2Bf=1
f=1-1%2F3-3%2F5
f=%2815-5-9%29%2F15
f=1%2F15
12 pounds is 1%2F15 of the mixture. That is, of the entire mixture. The mixture is therefore 15 times 12 pounds.

m for pounds of entire mixture,
12=%281%2F15%29m
m=12%2A15
highlight%28m=180%29