.
Their respective ages now are x+6 and x years.
In 3 years
(x+6) + 3 = 2(x+3)
x + 9 = 2x + 6
9 - 6 = 2x - x
3 = x.
ANSWER. Sophie is 3 years old; Thandi is 3+6 = 9 years old.
Solved.
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