Write number sentences for word problems with one addend unknown - up to 20
Free printable Grade 1 math worksheet for "Write number sentences for word problems with one addend unknown - up to 20" — practice addition and subtraction word problems up to 20. No-prep, print or assign online.
This worksheet provides students with word problems that require writing number sentences to find one unknown addend in addition problems up to 20. Teachers can use it to reinforce early addition skills and support understanding of equation structure. It is ideal for practicing addition strategies and building number sense with one addend missing.
Learning objectives
- Identify the missing addend in addition word problems with sums up to 20
- Write accurate number sentences representing word problems with one unknown addend
- Solve addition problems by determining the unknown addend using number sentences
Answer Key
How to use this worksheet
- Click “Download Worksheet” to get the PDF — free with a KiwiBee account (up to 25 downloads a month).
- Print at home or in class for Grade 1; it's no-prep, with no extra materials needed.
- Use the included answer key to mark it in seconds.
Frequently asked questions
Is the “Write number sentences for word problems with one addend unknown - up to 20” worksheet free?
Yes. “Write number sentences for word problems with one addend unknown - up to 20” is a free printable Math worksheet. Sign in with a free KiwiBee account to download the PDF — it includes up to 25 downloads a month.
What grade or age is this Math worksheet for?
It's designed for Grade 1 (ages 6–7), covering Addition and subtraction word problems up to 20.
Does it come with an answer key?
Yes — a matching answer key is included so you can grade it in seconds.
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