Question

do this please quickly

Answer 1

let their present ages be 5x and 7x ,
after 4 years,
$\frac{5x + 4}{7x + 4} = \frac{3}{4} \\ 20x + 16 = 21x + 12 \\ x = 4$
the present age of B = 7x = 28 years



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