One truck can move 8,400 tons of grain from the field in 60 hours, and another can carry

One truck can move 8,400 tons of grain from the field in 60 hours, and another can carry the same load in 84 hours. How long does it take when both trucks are working together?

1. First, let’s determine the operability of the first truck. To do this, we divide the number of tons of crop that needs to be transported by the number of hours of work:

P1 = 8400/60 = 140 (t / h).

2. Now let’s determine the operability of the second truck:

P2 = 8400/84 = 100 (t / h).

3. If trucks work together, then there is such a thing as overall performance. Let’s calculate:

P = P1 + P2 = 140 + 100 = 240 (t / h).

4. Let’s find the time during which both trucks, working together, will transport all the grain:

8400/240 = 35 (h).

Answer: it will take 35 hours.