Question

A student was 18 in. long when she was born. She is now 5 ft 6 in. tall and 20 years old. How many centimeters a year did she grow on average?

Answer 1

To calculate the average yearly growth in centimeters, we converted the student's height at birth and current height to centimeters found the difference, and divided it by her age, resulting in an average growth of about 6.096 centimeters per year.

Step-by-step explanation:

To calculate the average yearly growth in centimeters, we will first convert the heights to the same unit of measurement and then find the difference between the two measurements. Afterward, we divide this number by the age to find the average annual growth.

First, convert the birth height from inches to centimeters:
18 inches × 2.54 cm/inch = 45.72 cm.

Next, convert the current height into centimeters:
5 feet 6 inches = 5 × 12 inches + 6 inches = 66 inches
× 2.54 cm/inch = 167.64 cm.

Now, calculate the total growth in centimeters:
167.64 cm - 45.72 cm = 121.92 cm.

Finally, we find the average annual growth over 20 years:
121.92 cm / 20 years = 6.096 cm/year.

Therefore, the student grew on average about 6.096 centimeters per year.