Jim was thinking of a number. Jim adds 20 to it, then doubles it and gets an answer of 99.2. What wa

Discussion in 'Calculator Requests' started by math_celebrity, Jan 15, 2019.

  1. math_celebrity

    math_celebrity Administrator Staff Member

    Jim was thinking of a number. Jim adds 20 to it, then doubles it and gets an answer of 99.2. What was the original number?

    Start with x.

    Add 20 to it
    x + 20

    Double it
    2(x + 20)

    Set this equal to 99.2
    2(x + 20) = 99.2

    Divide each side by 2:
    x + 20 = 49.6

    Subtract 20 from each side:
    x = 29.6
     

Share This Page