The starting temperature was 0ºC. Then it dropped 4 times, until it was colder than -20ºC. Which inequality expresses the number of degrees, d, by which the temperature could have dropped each time?

Question

-4d ≥ -20
-4d < -20
-4d ≤ -20
-4d > -20

Answer 1

The correct inequality that expresses the number of degrees, d, by which the temperature could have dropped each time is: -4d > -20.

This is because if the temperature dropped 4 times, it would mean that it dropped by a certain number of degrees, represented by d, each time. Since the final temperature is colder than -20ºC, this means that the total drop in temperature must be greater than -20 degrees. Therefore, -4d (indicating the total drop in temperature) must be greater than -20.