Question

How many pairs of whole numbers have a sum of 110

Answer 1

There are different definitions of "whole numbers".

Some define it as an integer (i.e. positive or negative) [some dictionaries]

Some define it as a non-negative integer. [most math definitions]

We will take the math definition, i.e. 0<= whole number < &infin;

To find pairs (i.e. two) whole numbers with a sum of 110, we start with

0+110=110

1+109=110

2+108=110

...

54+56=110

55+55=110

Since the next one, 56+54=110 is the same pair (54,56) as 54+56=110, we stop at 55+55=110  for a total of 56 pairs.