9514 1404 393
Answer:
15 and 21
Explanation:
I like to work these considering the difference in ratio units.
The age ratio is 5 : 7.
The age difference in ratio units is 7 - 5 = 2. The difference in years is 6, so each ratio unit must be 6/2 = 3 years. Multiplying the ratio numbers by 3, we get the actual ages as ...
5 : 7 = (3·5) : (3·7) = 15 : 21
The two sisters are 15 and 21 years old.