Question

In City​ A, the temperature rises 4

degrees
°F from 8 A.M. to 9 A.M. Then the temperature drops 7
degrees
°F from 9 A.M. to 10 A.M. In City​ B, the temperature drops 6
degrees
°F from 8 A.M. to 9 A.M. Then the temperature drops 2
degrees
°F 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.

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

Answer 1

The general expression for the change in temperature between 8am and 10am

`\delta_(8-10)= \delta_(8-9) + \delta_(9-10)` where
`\delta` stands for change in the subscripted time interval.

For city A:

`\delta_(8-10) = 4 - 7 = -3\enspace ^\circ F`

For city B:

`\delta_(8-10) = -6 - 2 = -8\enspace ^\circ F`

In city A, there is an overall drop of 3 degrees (negative value). In city B, the temp drops 8 degrees.

Among A and B, city B has a greater change in temperature (8 vs. 3)