Question

use the rulers to answer the questions. write each answer as a whole number or decimal (not a fraction). (a) how much longer did the lizard grow from one month to the next? inches (b) at this rate, how long will the lizard be in month 14? inches

Explanation:

Step1: Measure lizard lengths

Let's assume the length of the lizard in month 9 is $l_9$, in month 10 is $l_{10}$, and in month 11 is $l_{11}$. From the ruler, if $l_9 = 32$ inches, $l_{10}=34$ inches, $l_{11} = 36$ inches.

Step2: Calculate monthly growth

The growth from month 9 to month 10 is $l_{10}-l_9=34 - 32=2$ inches. The growth from month 10 to month 11 is $l_{11}-l_{10}=36 - 34 = 2$ inches. So the lizard grows 2 inches from one - month to the next.

Step3: Calculate length in month 14

There are $14 - 11=3$ more months from month 11 to month 14. Since the lizard grows 2 inches per month, the additional growth is $2\times3 = 6$ inches. The length of the lizard in month 11 is 36 inches. So the length in month 14 is $36+6=42$ inches.

Answer:

(a) 2
(b) 42