Question 879694
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Hi
Let x represent sister's age
Question States***3 years ago...
2x - 3 = 3(x-3)
 2x- 3 = 3x-9
     6 = x, the sister's age.  Bother is 12 {{{2*6}}}
CHECKING our answer***3 years ago...
 {{{9 = 3*3}}}
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