Question 1145860
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When Scott was 4 times as old as Shannon, let their ages be 4x and x.  The difference in those ages is 4x-x = 3x.<br>
The difference in their age is given as 24-12 = 12.<br>
We want to find when the difference of 12 years in their ages was equal to 3x:
3x = 12
x = 4<br>
Scott was 4 times as old as Shannon when she was x=4 and he was 4x=16.<br>
Since they are now 24 and 12, that was 8 years ago.