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Meteorologists in Atlanta have developed the following equation to estimate the temperature t, in degrees Fahrenheit, based on the number of hours h after sunrise until 4:00 PM:

t = 5h + 61.4

According to this model, by how many degrees Fahrenheit will the temperature rise each hour until 4:00 PM?

a) 3.3

b) 5

c) 12.3

d) 30.7

The answer is b, 5 degrees. The equation means that the temperature will be 61.4 degrees + 5 degrees each hour until 4 pm.

Answer: b) 5

Explanation:

The equation for the temperature in Fahrenheit is:

t = 5h + 61.4

Where h is the number of hours after 4:00 pm

then if this is compared with a linear equation, the y-intercept is 61.4 Fahrenheit, and the slope is 5 Fahrenheit/hour

Now we want to know by how many degrees Fahrenheit will the temperature rise each hour until 4:00 PM, we need to look at the slope in order to answer this.

We know that the slope is 5 Fahrenheit/hour, so each hour that passes the temperature increases by 5 degrees Fahrenheit.

The right option is b) 5.