Question

Two is subtracted from a number, and then the difference is multiplied by 5. The result is 30. What is the number?

Answer 1

x = unknown number

x-2 = subtract off 2

5(x-2) = multiply by 5

5(x-2) = 30

Let's solve for x. Follow PEMDAS in reverse to undo each operation until x is isolated.

5(x-2) = 30

x-2 = 30/5

x-2 = 6

x = 6+2

x = 8

Another approach is this set of steps

5(x-2) = 30

5x-10 = 30

5x = 30+10

5x = 40

x = 40/5

x = 8

Answer: The unknown number is 8