Trying to use the IF function to get a cell to generate a "grade" based on a
number of points, e.g.:

IF the contents of B1 are less than 40, then B2 will read "A"
IF the contents of B1 are greater than or equal to 41, BUT less than 71,
then B2 will read "B"
IF the contents of B1 are greater than or equal to 71, then B2 will read "C".

Can't get this to work. Am currently using three cells with IF formula, with
the idea that they'll either read A or xxx, B or xxx or C or xxx (to
accommodate the true or false requirements of the IF function), but I think
I'm going about it ALL wrong.

What I really want to do, basically, is get a formula that reads the number
in a single cell, and gives me one of three letter values in another cell
based on the numerical value of the first cell.

This is driving me **bats**.

Any suggestions?