What would it be like to use egyptian fractions for arithmetic? We would want algorithms for addition, subtraction, multiplication, division, floor, compare, and canonicalization. And maybe converting to decimals. Of course all of these can be done by converting the EF to standard rational num/den representation, doing the arithmetic, and then converting back. But it's an interesting problem to give algorithms that preserve the spirit of the representation as much as possible. For addition, we can take the multiset union of the addends, and then apply some algorithm for getting rid of the 2/n terms. Or we might provide a subalgorithm for adding 1/n to a generic EF. Subtraction and comparison raise similar problems. Providing methods that don't dramatically blow up the number of terms and the largest denominators seems challenging. Rich rcs@cs.arizona.edu