A dump truck brought 1/3 of a ton of rock on the first trip, 1/2 of a ton on the second trip, and 4/5 of a ton on the third trip. What was the total weight of the rock?

The answer is 1 19/30

We'll have to convert the denominators to a number that each of these three will add in to.

We'll use 30, since we can use 15 as we have a denominator of 2.

1/3 = 10/30

4/5 = 24/30

1/2 = 15/30

Now, we just add all the numerators

49/30

1 and 19/30

19 does not evenly divide into anything.

You answer is 49/30, or 1 and 19/30