Subtraction, missing numberUp to 20
Name: Date:
120 − = 0
2 − 2 = 10
320 − = 13
49 − = 1
516 − = 8
6 − 16 = 3
7 − 18 = 2
85 − = 5
9 − 1 = 0
1013 − = 11
Missing number subtraction worksheets
These free printable worksheets blank out one number in a subtraction sentence within twenty — sometimes the number you start with, sometimes the number taken away — so a child has to reason about the whole relationship instead of following a procedure.
If they get stuck
Missing number subtraction
The answer key prints on a separate page.
What's on this sheet
The two blanks are genuinely different problems. Finding the missing subtrahend in 15 − __ = 8 is a counting-up question: how far from 8 up to 15? Finding the missing minuend in __ − 6 = 9 runs the other way and is solved by adding. A child who has met both stops treating the minus sign as an instruction to always subtract whatever they can see.
Why this sheet works
This is where subtraction as difference finally earns its keep. Counting up from the smaller number is usually faster and less error-prone than counting back, and a page of gaps makes that strategy the obvious one to reach for. Children who only meet take-away problems rarely discover it on their own.
How this one works
One question from a sheet like this one, worked a step at a time — with a sentence saying what just happened and why.
Missing number subtraction, step by step