Addition & subtractionGrade 1
Subtraction with Regrouping practice
Subtract a one-digit number from a teen number when the ones digit is too small, such as 13 − 6. You borrow from the ten.
Example problems
12
−
8
＝
4
12
−
9
＝
3
13
−
6
＝
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.