Grade 1 · Numbers & operations

Subtraction facts within 20 practice

Subtraction facts within 20 is a grade 1 math skill aligned to Common Core standard 1.OA.C.6: add and subtract within 20, demonstrating fluency for addition and subtraction within 10. Below are 8 practice questions with answers and step-by-step explanations, drawn from the 200 subtraction facts within 20 problems our math games drill.

CCSS 1.OA.C.6200 questions in the bank
Sample questions

Try 8 for free

Question 1easy

What is 13−813 - 8?

13−8=513 - 8 = 5.

Question 2easy

What is 11−1111 - 11?

11−11=011 - 11 = 0.

Question 3easy

What is 0−00 - 0?

0−0=00 - 0 = 0.

Question 4easy

What is 9−39 - 3?

9−3=69 - 3 = 6.

Question 5easy

What is 12−112 - 1?

12−1=1112 - 1 = 11.

Question 6easy

What is 12−1012 - 10?

12−10=212 - 10 = 2.

Question 7easy

What is 1−01 - 0?

1−0=11 - 0 = 1.

Question 8easy

What is 9−29 - 2?

9−2=79 - 2 = 7.

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Games that drill subtraction facts within 20

These games serve this exact skill as live head-to-head matches.

Balloon Pop Math gameBalloon Pop MathPop balloons. Solve math. Win!Beam Team gameBeam TeamFly your saucer over the night farm and beam up a critter for every right answer — first to 12 wins.Blaster Gate gameBlaster GateBlast through the wall. First to clear wins.Blitz Tanks gameBlitz TanksSolve math to load shells. Out-think the battalion. Last math standing wins.
Tests that cover subtraction facts within 20:
i-ReadyISIP MathMAP Growth
More Grade 1 skills:
Missing addendTen more / ten lessAddition facts within 20All Grade 1 practice →

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