Question

Dequan is making homemade ice cream which needs to be frozen gradually to achieve the best texture. When he starts, the temperature of the ice cream is 50°F. The temperature drops 5°F each hour for the next 3 hours. Dequan then puts it in a deep freezer causing the temperature to drop 13°F. Which integer best represents the change in the temperature of the ice cream from start to finish? -28°F -28°F -13°F -13°F 13°F 13°F 28°F

Answer 1

The change in the temperature of the ice cream from start to finish is -28°F

Explanation:

From the question,

Initial temperature of the ice cream is 50°F.

Also, the temperature drops 5°F each hour for the next 3 hours; that is for every hour in the next 3 hours, the initial temperature decreases by 5°F.

Then after 3 hours, the initial temperature would have decreased by 3 × 5°F;

3 × 5°F = 15°F

Hence, after 3 hours, the temperature of the ice cream would be 50°F -15°F;

50°F - 15°F = 35°F

After 3 hours, the temperature of the ice cream would be 35°F.

From the question,

Dequan then puts it in a deep freezer causing the temperature to drop 13°F

Now, the final temperature of the ice cream is 35°F - 13°F = 22°F

The final temperature of the ice cream is 22°F.

To determine the change in the temperature of the ice cream from start to finish,

Change in temperature = Final temperature - Initial temperature

Change in temperature = 22°F - 50°F = -28°F

Hence, the change in the temperature of the ice cream from start to finish is -28°F.