[Solved] Bash test 2 variables to see if ones greater by n

Experts,
I have a bash shell script that generates 2 variables that have the current minute and a minute from a log file. Can someone please show me the best way to test if the minutes stray by 5. So basically if:
This is ok:

Last Fitting Min
=============
02
Current Minute
=============
02

This is bad:

Last Fitting Min
=============
02
Current Minute
=============
07

I know how to test if the values are greater than each other. However I am unsure how to check if the value is greater by 5.

I hope I explained this well enough.
Here are the system details.

Kernel: 2.6.18-194.el5
GNU bash, version 3.2.25(1)-release (x86_64-redhat-linux-gnu)
Copyright (C) 2005 Free Software Foundation, Inc.

Hi.

$ A=2
$ B=7
$ [ $((B-5)) -ge $A ] && echo Oh no   
Oh no
$ B=2                             
$ [ $((B-5)) -ge $A ] && echo Oh no
$ 

(by 5 or more. Replace -ge to -eq for exactly 5)

Thanks for the quick reply. This is what I need.
Please mark solved.