Answer:
17, 19 and 21
Step-by-step explanation:
Consecutive odd numbers mean odd numbers that are right next to each other.
Eg: 3, 5, 7
Let x represent the youngest sister. The sister older than her will be 2 years older than her, hence (2 + x). The oldest sister would be 4 years older than the youngest and two years older than the middle sister, hence (4 + x).
The sum of their age = 57.
Hence:
x + (2 + x) + (4 + x) = 57
x + 2 + x + 4 + x = 57
Simplify
3x + 6 = 57
Rearrange
3x = 57 - 6
3x = 51
Divide both sides by 3 to make x on its own (this way we can find the age of the youngest sister).
x = 17 (youngest sister is 17 years old)
x + 2 = 19 (middle sister is 19 years old)
x + 4 = 21 (oldest sister is 21 years old)
