Adding =If(B3<D3,"" to existing formula

[Richard]

=IF(ISERROR('Tank Sizes'!$F$30-('Tank Sizes'!$F$30/B3))/3.79,"",('Tank
Sizes'!$F$30-('Tank Sizes'!$F$30/B3))/3.79)

How do I add =If(B3<D3,"" to this formula
I don't want the results to show up if it's a negative number.
Thanks in Advance!

 

[Pete_UK]

As well as adding that snippet plus a comma to the beginning, you will
also have to add a closing bracket to the end, like this:

=IF(B3<D3,"",IF(ISERROR('Tank Sizes'!$F$30-('Tank Sizes'!$F$30/B3))/
3.79,"",('Tank Sizes'!$F$30-('Tank Sizes'!$F$30/B3))/3.79))

but you can simplify the formula slightly, like this:

=IF(B3<D3,"",IF(ISERROR('Tank Sizes'!$F$30*(1-1/B3)),"",('Tank Sizes'!
$F$30-'Tank Sizes'!$F$30/B3)/3.79))

Hope this helps.

Pete