in City​ A, the temperature rises 4degreesF from 8 A.M. to 9 A.M. Then the temperature drops 7degreesF from 9 A.M. to 10 A.M. In City​ B, the temperature drops 6degreesF from 8 A.M. to 9 A.M. Then the temperature drops 2degreesF from 9 A.M. to 10 A.M. Write an expression that represents the change in temperature from 8 A.M. to 10 A.M. for each city. Simplify and interpret each sum.

Question

Use pencil and paper. Which city has the greater change in​ temperature?

Which expression represents the change in temperature for City​ A?

Answer 1

To determine the change in temperature from 8 A.M. to 10 A.M. for each city, we can create expressions based on the temperature changes throughout that time frame.

City A:

1. Temperature change from 8 A.M. to 9 A.M.: The temperature rises by 4°F.
2. Temperature change from 9 A.M. to 10 A.M.: The temperature drops by 7°F.

Now, we can create the expression for City A:

\[ \text{Change in Temperature for City A} = 4 + (-7) \]

This simplifies to:

\[ 4 - 7 = -3 \]

Thus, the overall change in temperature for City A from 8 A.M. to 10 A.M. is a drop of 3°F.

City B:

1. Temperature change from 8 A.M. to 9 A.M.: The temperature drops by 6°F.
2. Temperature change from 9 A.M. to 10 A.M.: The temperature drops by 2°F.

Now, we can create the expression for City B:

\[ \text{Change in Temperature for City B} = -6 + (-2) \]

This simplifies to:

\[ -6 - 2 = -8 \]

Thus, the overall change in temperature for City B from 8 A.M. to 10 A.M. is a drop of 8°F.

Summary:

• Change in temperature for City A: -3°F
• Change in temperature for City B: -8°F

Conclusion:

City A has a lesser change in temperature (a drop of 3°F) compared to City B (a drop of 8°F). Therefore, City A has the greater change in temperature when considering how much the temperature rose or fell!