18
you need to add 3/10 to 7/10 to get 10/10 or 1.
add 9 plus 5 than subtract 1 from 5 to add it to 9 will give you 10
19
9 and 9
10 - (-9) = 19
10
you need 11 more.
You need to add 6 - (-9) = 6 + 9 = 15.
you need to add +9 +9-7 = +2
19
18
You need to add 18 to negative 8 to get 10.
you need to add 10
When you add -9 and +10, you get (+) 1.
you need to add 3/10 to 7/10 to get 10/10 or 1.
19