Question

At Paul Bunyan’s tree farm they sell Fraser firs and blue spruce trees. They plant saplings of these two kinds of trees that are 8 inches in 5 inches tall, respectively. The Fraser firs grow at a constant rate of 12 inches per year, and a blue spruce trees grow at a constant rate of 14 inches per year. After how many years will these trees be at the same height? Express your answer as a common fraction.

Answer 1

8 + 12y = 5 + 14y

12y + 8 = 14y + 5

12y + 8 - 8 = 14y + 5 - 8

12y = 14y - 3

12y - 14y = 14y - 3 - 14y

-2y = -3

(-2y)/-2 = -3/-2

y = 3/2

Answer 2

Answer: 3/2

Explanation:

Hi, to answer this question we have to write the next expressions::

Height 1= 8 +12 y

Height 2 =5 +14y

Where y = number of years

Since both heights must be the same

Height 1 = height 2

8+12y = 5+14y

solving for y:

8-5 =14y-12y

3 = 2y

3/2 =y

y = 3/2 years

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