Question

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?

Answer 1

1/30 ton of rock left

Explanation:

1/3+ 1/2= 5/6

5/6 - 4/5= 1/30 ton of rock left at the construction site.

Answer 2

1/3 + 1/2 + 4/5

The least common multiple of 3, 2, and 5 is 30

1/3 * 10/10 = 10/30
1/2 * 15/15 = 15/30
4/5 * 6/6 = 24/30

10/30 + 15/30 + 24/30 equals
49/30 tons or 1 and 19/30 tons