Question 325325
let mother's age =x
husband = x+9
..
son = x/2 
sister 1/3 (x+9)
brother = 1/3(x+9)+7
..
brother = son
..
x/2 = 1/3(x+9)+7
3x/2 = x+9+7
3x/2 = x+16
3x= 2(x+16)
3x=2x+32
3x-2x=32
x= 32 mother's age.