Decrease = (original number - new number) / original number .....x 100
decrease = (49 - 22) / 49.....* 100 =
(27 / 49) * 100 =
2700 / 49 = 55% decrease
The average yearly growth rate of the height of the tree was 2.2 feet per year during the 7 1/2 years.

P.S. Hello from Russia :^)

Solution:
Given data:
and 
To find F(x) + G(x):
Adding two functions which gives another function.
Substitute F(x) and G(x), we get





Hence, 