Answer:
24 and 32
Step-by-step explanation:
Let their present ages be x and y
Therefore, x
[tex] \frac{x}{y} = \frac{3}{4} [/tex]
we have 4x = 3y
4x - 3y = 0......................(I)
After four years,
[tex] \frac{x + 4}{y + 4} = \frac{7}{9} [/tex]
we have, 9(x + 4) = 7(y + 4)
9x + 36 = 7y + 28
9x - 7y = -8 ........................(ii)
Solving (I) and (ii) simultaneously
4x - 3y = 0
9x - 7y = -8
multiply eqn I by 9 and equation (ii) by 4 and subtract result
36x - 27y = 0...............(iii)
36x - 28y = -32...........(iv)
subtracting (iv) from (iii) we have,
y = 32
substituting y back in equation (I)
4x - 3y = 0
4x -3(32) = 0
4x - 96 = 0
4x = 96
x = 24
Their ages are 24 and 32