Eustace is twice as old as Milford. In 3 years, he will be 39. How old will Milford be?
Eustace’s current age must be 39 years old – 3 years = <<39-3=36>>36 years old.
So Milford’s current age must be 36 years old / 2 = <<36/2=18>>18 years old.
So in 3 years, Milford will be 18 years old + 3 years = <<18+3=21>>21 years old.
#### 21