The number of 3-digit numbers, that are divisible by 2 and 3, but not divisible by 4 and 9, is  

No, of 3 digits = 999 – 99 = 900 
No. of 3 digit numbers divisible by 2 and 3 i.e. by 6 
$\frac{900}{6}=150$
No. of 3 digit numbers divisible by 4 and 9 i.e. by 36
$\frac{900}{36}=25$
$\therefore$ No of 3 digit numbers divisible by 2 and 3 but not by 4 and 9 
150 – 25 = 125