12 and 21
It is not possible to express something as a sum of whole numbers with no common factor. All whole numbers have at least 1 as a common factor.
20 and 24
Answer: 276
=The two numbers to this question are 40 and 50.=
36 and 60.
45 and 10
It is 15*(1 + 2)
48 and 36
try 45 and 10 maybe?
12 and 20
336 and 48
I think I know what you're asking, but it doesn't work like that. The sum of any set of numbers is a single number and single numbers don't have common factors until they are compared to at least one other number. The sum of three consecutive counting numbers will be at least a multiple of 3.