How old is she today?

Question

In another four years Winnie will be three times as old as she was four years ago. If it is Winnie's birthday, how old is she today?

Answer 1

Let x=Winnie's age today

 

Translate:

  "In another four years Winnie will be three times as old as she was four years ago"       means

          x     +  4                           =       3       *                          (x - 4)

 

  x+ 4 = 3*(x-4)                        [rewrite]

  x +4 = 3x - 12                         [distribute]

  -2x = -16                               [subtract 3x + 4 from each side]

     x = 8                                 [divide each side by -2]

Answer 2

x=Winnie's age today

x+4=3(x-4)

x+4=3x-12

4+12=3x-x

16=2x

x=16/2

x=8 years old today