Answer:
The required fraction is 17/60
Step-by-step explanation:
Consider the provided information.
Let us assume that the number number if trees are 60.
It is given that 20% are apple tree.

Therefore, 12 trees are apple tree.
That means non apple trees are:
Non apple trees = 60 - 12 = 48
It is given that and 1/3 of the trees that are not apple trees are cherry trees.
Cherry trees = 1/3 × 48 = 16
The cherry trees are 16.
3/4 of the trees in the orchard are fruit trees,
Fruit trees = 3/4 × 60 = 45
Total fruit tree are 45
Plum trees = 45 - 12 - 16 = 17
Hence, the number of plum trees are 17
We need to find fraction of the trees in the orchard are plum trees
Fraction = 17/60
Hence, the required fraction is 17/60