If you add 0.39 to 0.61 you get 1
if you add 1+1 it = 2 get it :D
(7+1) and (7-1)
You cannot add 3x and 1. You can add 3x and x and get 4x though.
1 and a half add 1 and two thirds = 2
It is: 33+211+1 = 245
add 9 add 1 subtract 20 add 9 add 1
because if you add 1 to 12 you will get one more not less.
12, 13, 16 Add three, then add 1, then add three, then add 1, and so on so forth
1
2
You start with 1 and add 1. add another 1 and another. In all, do the addition 9,999,999,999 times.