How can I make the if function check the variable number for the number I need from 100-200?

[yod4]

I'm doing a number check, I need the script logic to be such that if the number in the variable was greater than 300 but less than 600, then it would do the function, if the opposite would include another check

[BAS Viet Nam]

@yod4

[[NUMBER]] > 300 && [[NUMBER]] < 600