Answer : 1/2 gallon
Step-by-step explanation:
There were a total of 5 gallons collected, as the question states.
There are 3 x's above 1/4, 2 x's above 3/8, 4 x's above 5/8 and 1 x above 1. This is a total of
3+2+4+1 = 10 x's. This means there were 10 trees.
If 5 gallons is evenly distributed among 10 trees, this would give us the ratio 5/10, which simplifies to 1/2 gallon per tree.
....this answer is not from me. The same question was asked on brainy and I've copy pated it, it is the right answer tho. Credit goes to "MsEHolt" for answering.