<h3>
Answer: 78.6</h3>
Work Shown:

Multiply across the rows to form a third column. Example: 9*90 = 810 in the first row.

The values in the third column add to 810+1440+1050 = 3300
Divide this over the total number of people which is 9+18+15 = 42
The mean is 3300/42 =78.571 approximately which rounds to 78.6
It will take 6 years for the trees to have same height.
Step-by-step explanation:
Type A tree;
Initial height = 9 feet
We will convert feet into inches because growth is in inches.
1 feet = 12 inches
9 feet = 12*9 = 108 inches
Growth rate = 6 inches per year
Let,
x be the number of years.
A(x) = 108 + 6x
Type B;
Initial height = 4 feet = 4*12 = 48 inches
Growth rate = 16 inches per year
B(x) = 48 + 16x
The height will be same, when functions are equal
A(x) = B(x)

Dividing both sides by 6

It will take 6 years for the trees to have same height.
Keywords: function, division
Learn more about division at:
#LearnwithBrainly
Answer:
Step-by-step explanation:
