All I know is my math teacher would have had a fit if I wrote 2/20=6/20. Can anyone help decipher WIX's information of these 2 filters.

WIX uses their own non-industry beta ratio nomenclature. That's what screws up trying to understand WIX beta ratio numbers, because it doesn't follow what you're gonna find searching the internet.

2/20=6/20

The two numbers on the left of the equals sign are the Beta Ratios:

Beta 2 = 50% efficient

Beta 20 = 95% efficient

The two numbers on right of the equals sign are the corresponding particle sizes.

The 2 in "2/20" goes with the 6 in "6/20", so it means 50% efficient at 6 microns.

The 20 in "2/20" goes with the 20 in "6/20", so it means 95% efficient at 20 microns.

Think of it as:

Beta 2/Beta 20 = 6 microns/20 microns

or

50% at/95% at = 6 microns/20 microns