Question

Mr. Garrison purchases a new freezer. The current temperature in the freezer is 21°C, and it needs to reach -18°C. If the temperature decreases at a rate of 3° per hour, how long will it take to reach -18°C?

A. 13 hours
B. 13.5 hours
C. 12.5 hours
D. 14 hours

Answer 1

It will take 13 hours for the freezer to reach -18°C.

Step-by-step explanation:

To find out how long it will take for the freezer to reach -18°C from an initial temperature of 21°C, we need to calculate the temperature difference and divide it by the rate of temperature decrease.

The temperature difference is 21°C - (-18°C), which simplifies to 39°C.

Since the temperature decreases at a rate of 3°C per hour, it will take 39°C / 3°C per hour = 13 hours to reach -18°C.