Question

question 5 of 10
a scientist measures the growth of a bamboo plant over time. the table below shows the results.

time (hours)	height (cm)
20	1.5
30	1.8
40	2.1
50	2.4
60	2.8

what is the best inference for the height of the plant after 15 hours?

a. 1.55 cm
b. 1.20 cm
c. 1.50 cm
d. 1.35 cm

Explanation:

Step1: Find the rate of growth between 10 - 20 hours

The growth from 10 hours (height = 1.2 cm) to 20 hours (height = 1.5 cm) is $1.5 - 1.2=0.3$ cm in 10 hours. The rate of growth $r=\frac{0.3}{10}=0.03$ cm per hour.

Step2: Calculate the growth from 10 to 15 hours

The time - interval from 10 to 15 hours is 5 hours. Using the rate $r = 0.03$ cm per hour, the growth in 5 hours is $0.03\times5 = 0.15$ cm.

Step3: Find the height at 15 hours

The height at 10 hours is 1.2 cm. Adding the growth from 10 to 15 hours, the height at 15 hours is $1.2+0.15 = 1.35$ cm.

Answer:

D. 1.35 cm