No they're not proportionate because 9 divided by 4 = 2.25 and 11 divided by 6 is 1.83 so they're not the same in value
Left side: 63, 72, 16 right side: 36, 4, 35
X - Ollie's age
8 is subtracted from Ollie's age = x-8
the result is the same as
subtracting 16 from 3 times his age = 3x-16

Ollie is 4 years old.