Denise will be 25 years old in two years. Her sister, Diane, is 4 years younger. In how many years will Diane be 25 years old?
How old is Denise now? ** Denise is 25 - 2 = <<25-2=23>>23 years old now.
How old is Diane now? ** So, Diane is 23 - 4 = <<23-4=19>>19 years old now.
How old will Diane be in 6 years? ** Diane will be 25 years old in 25 - 19 = <<25-19=6>>6 years.
#### 6