22
21
-1
3/21 + 7/21 = 10/21
The factors of 21 that add up to 8 are 1 and 7.
21, 21, 21, 21 , 15, 1
20 + 1
How do you add 9, 5, 3, and 1 in such a way to get sum of 21 by using only 6 numbers?You would add 9+5+3+1+1+2 and your answer would be 21.
1 and -1 if you add them. 1 and 1 if you subtract them.
22
41
-21 and -1
Just add 20 then add 1 eg 2142 64