I know less than is to describe the relationship between two words. However I found another usage that is "A is 2 less than B". Does it mean
A = 2 - B,
A = B - 2 or other meaning?
This kind of phrase is often used in tests and can trip even the most seasoned reader if only a casual assessment is made. In effect, this is a verbal representation of an equation.
"A is" allows for the basis of the resolution, "A = ".
"2 less than B" expresses a value of B, less 2, to assign to A, eg "B - 2".
Note here that the entire context of evaluation changes if something as simple as "than" is omitted, eg "2 less B", which would result in "2 - B".
The correct evaluation is "A = B - 2".