Question

The temperature in Jeff's city is 58° and

is rising 0.5° degrees each hour The
temperature in Amber's city is 61° and is
rising 0.25° each hour. After how many
hours will the temperatures in Jeff's and
Amber's cities be the same?

Answer 1

12 hours.

Explanation:

Let y = the current temperature

Let x = the number of hours

Jeff's city

y = .5x + 58

Amber's city

y = .25x + 61

Set the two equations equal to each other and solve for x.

.5x + 58 = .25x + 61 Subtract .25x from both sides of the equation

.5x - .25x + 58 = .25x - .25x + 61

.25x + 58 = 61 Subtract 58 from both sides of the equation

.25x + 58 - 58 = 61 - 58

.25x = 3 Divide both sides by .25

`(.25x)/(.25)` =
`(3)/(.25)`

x = 12

In 12 hours the temperatures will be the same.

Check:

y = .5x + 58

y = .5(12) + 58

y = 6 + 58

y = 64

y = .25x + 61

y = .25(12) + 61

y = 3 + 61

y = 64

In 12 hours, both cities will be at 64°