Question 1137518
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The difference in their ages will always be 2 years.<br>
If the sum of their ages 3 years ago was 48, the sum of their ages now is 48+2(3) = 54.<br>
If the sum of their ages is 54 and the boy is 2 years younger than his sister, simple logical reasoning tells us the boy is 26 and his sister is 28.