Question

A gardener is planting two types of trees:

Answer 1

It takes 12 years for both trees to be of same height

Solution:

Assume the year that it would take to these trees have the same height is : x (years)

Type A is 7 feet tall and grows at a rate of 23 inches per year:

Convert 7 feet to inches

We know that,

1 foot = 12 inch

7 feet = 12 x 7 inch = 84 inch

Thus, type A is 84 inches tall and grows at a rate of 23 inches per year

We can frame a equation as:

Type A = 84 + 23(number of years)

Type A = 84 + 23x ---------- eqn 1

Type B is 5 feet tall and grows at a rate of 25 inches per year

Convert 5 feet to inches

5 feet = 5 x 12 inches = 60 inches

Thus, type B is 60 inches tall and grows at a rate of 25 inches per year

We can frame a equation as:

Type B = 60 + 25(number of years)

Type B = 60 + 25x --------- eqn 2

For both the trees to be of same height, eqn 1 must be equal to eqn 2

84 + 23x = 60 + 25x

25x - 23x = 84 - 60

2x = 24

x = 12

Thus it takes 12 years for both trees to be of same height