Given:
Serenity picked 75% of the apples of a tree in her backyard.
She picked 30 apples.
To find:
The number of apples on the tree in the beginning.
Solution:
Let x be the number of apples on the tree in the beginning.
Serenity picked 75% of the apples of a tree in her backyard.
Number of apples picked = 75% of x
=
=
She picked 30 apples.
Multiply both sides by 4.
Divide both sides by 3.
Therefore, the number of apples on the tree in the beginning is 40.