Question

When Derek planted a tree it was 36 inches tall. The tree grew 1/1/4 inches per year. The tree is now 44/3/4 inches tall. How many years ago did Derek plant the tree? A 7   B 8   C 9   D 10

Answer 1

36 inches = 1st year
44.75 inches - 36 inches = 8.75 inches
Meaning it grew 8.75 inches

Since it grew 1.25 inches per year,
$8.75 \div 1.25 = 7$
Derek planted the tree 7 years ago.
The answer is A.

Hope this helps.