Question

The daily lowest temperature, in degrees Fahrenheit, for a certain week are -2, -3, x, 2x, 4, 8. For the week, the sum of the temperatures was -7°F.What is the value of x?

Answer 1

-14/9

Explanation:

Combine -2, -3, x, 2x, 4, 8. We get -5 + 3x + 12. This sum is -7.

Solve this equation for x: 3x + 7 = -7, so 3x = -14/3.

Then x is -14/9.

Answer 2

-4.7

Explanation:

-2 + (-3) + x + 2x + 4 + 8 = -7

-5 + 3x +12 = -7

3x + 7 = -7

3x = -14

x = -14/3 = -4.7 °F

The value of x is -4.7.

Check:

-2 + (-3) + (-4.7) + 2(-4.7) + 4 + 8 = -7

-5 - 4.7 - 9.3 + 12 = -7

-7 = -7

OK