Human: Djibo is 17 years old. Five years ago Djibo added his age with his sister's age and the sum was 35. How many years old is Djibo's sister today? Assistant: 
How old was Djibo 5 years ago? ** Age 5 years ago: 17 - 5 = <<17-5=12>>12
How old was Djibo's sister 5 years ago? ** Sister's age 5 years ago: 35 - 12 = <<35-12=23>>23
How old is Djibo's sister today? ** Sister's age today: 23 + 5 = <<23+5=28>>28 years
How old is Djibo's sister today? ** Djibo's sister is 28 years old today.
#### 28