<PRE><B>Question 1147795</B>
&lt;br&gt;
(1) Algebra....&lt;br&gt;
let x be his sister&#39;s age
then x+8 is his age&lt;br&gt;
His sister&#39;s age 3 years from now will be x+3; his age 3 years from now will be x+11.&lt;br&gt;
3 years from now, his age will be twice his sister&#39;s age:&lt;br&gt;
{{{x+11 = 2(x+3)}}}&lt;br&gt;
Solve using basic algebra (I leave that to you).&lt;br&gt;
(2) Logical reasoning....&lt;br&gt;
Since the difference in their ages is 8 years, Frank will be twice as old when he is 16 and his sister is 8.  Since that will be 3 years from now, their current ages are 13 and 5.&lt;br&gt;
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