SOLUTION: 16. Construction: Concrete weighs 150 lb/cu ft. What is the weight of a concrete wall 18 ft. long, 4 ft 6 in. high, and 8 in. thick?

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Question 108274: 16. Construction: Concrete weighs 150 lb/cu ft. What is the weight of a concrete wall 18 ft. long, 4 ft 6 in. high, and 8 in. thick?
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

let length be a,
let height+ be b
and let thickness be c

Given:
a+=+18+ft. , b+=+4+ft-+6+in , and c+=+8+in
concrete-+weighs=+150+%28lb%2Fft%5E3%29
volume+=a%2Ab%2Ac
8in+=+0.666665ft+=+0.67ft
6in+=+0.499999ft+=+0.5

Then, we have:

a+=+18+ft. , b+=+4.5+ft , and c+=+0.67ft

So,
volume+=a%2Ab%2Ac

volume+=18ft%2A4.5ft%2A0.67ft

volume+=18ft%2A4.5ft%2A0.67ft

volume+=+54.27ft%5E3
Since concrete-+weighs=+150+%28lb%2F+ft%5E3%29

= >150+%28lb%2Fft%5E3%29%2A54.27ft%5E3+…….cancel ft%5E3

=> the-+weight-+of-+a-+concrete-+wall+=+150lb%2A54.27+=+8140.5lb