Addition & subtractionGrade 1
Addition with Regrouping practice
Add two one-digit numbers that cross 10, such as 8 + 9 = 17. This is where a sum first carries into the tens place.
Example problems
3
＋
8
＝
1
1
9
＋
3
＝
1
2
8
＋
9
＝
1
7
How a practice round works
A round has 10 problems from this skill. Type the digits into the dotted boxes; if a digit is wrong, you simply try again. Get 5 of your last 6 problems right on the first try to master the skill, then keep practicing to earn up to three stars.