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15 votes
15 votes
A dump truck brought 1⁄3 of a ton of rock on the first trip, 1⁄2 of a ton on the second trip, but on the third trip, had to take back 4⁄5 of a ton. What was the total weight of the rock left at the construction site?

User Alex Waters
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1 Answer

19 votes
19 votes

Answer:

1/30 of a ton of the rock was left at the construction site

Hope this helps :)

Explanation below.

Explanation:

1. Make the same denominators to add them which is 6 (LCM).

1/3 + 1/2

2/3 + 3/6 = 5/6

2. Make the same denominator to subtract them since had to take back 4/5 of a ton. 30 would be the Least Common Multiple of 6 and 5.

5/6 - 4/5

25/30 - 24/30 = 1/30

User Mohammad Roshani
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