select a5:a17 range, and on the formula is of the cond format use

=a5=$a$1

format as you need.

hth
--
pleae click yes if it was helpfull
regards from Brazil
Marcelo



"Jim" escreveu:

Hello,

I understand how conditional formatting works but can't seem to figure out a
formula - will you please help?

What formula would I use in order to change the format of cells A5:A17 if
the number is equal to or greater than A1?

Thanks