Respuesta :

mathmate
Given: sum=21, difference=3

Sum and difference problem.
Then
larger number = (sum+difference)/2=(21+3)/2=12
smaller number = (sum-difference)/2 = (21-3)/2=9

bsekna
12+9= 21

To find this answer I first started off with a template: 18+3 (which equals 21).

After this, I divided 18 by 2 and added the 3 to my quotient, which gave me the 12. As for the other 9, I used that to add by 12.

12-9=3

So, the answer is 12+9=21