Question

The average growth of a person’s hair is approximately 12 inches every 6 months.

a) What is the constant of proportionality equation that represents the amount of hair growth per month?


b) Using the information from A, how many months will it take for her hair to grow 2 feet?


c) Using the information from A, how many inches will the hair grow after 2 years?

Answer 1

(A) Growth/month= 2inches * X (X represents number of months)

(B) It will take 1 year to grow 2 feet of hair

(C) The hair will grow 4 feet in 2 years

Explanation:

(A) The variable in the equation is number of months as the growth per month is constant

(12 inches/ 6 months).

In this case the equation is simple as

Multiplying the growth per month with number of months will give you total growth.

Hence the equation will be

Growth= 2inches( growth/ month) * "X" ( number of months)

(B) Using the same equation

First lets convert 2 feet into inches

One feet consists of 12 inches

So: 12*2= 24inches

Growth =24 inches

Growth/month= 2 inches

Months= X

1. 24= 2 * X

2. X= 24/2

3. X= 12 months

(C) Using the same first lets convert 2 years into months

(12*2=24months)

Calculation

Growth= 2 * 24

Growth = 48 inches

Which in feet would be (48/12=4) 4 feet