IXL | Write number sentences for word problems with change unknown - up to 20

Read the story.

At a fire station, there were 11 fire trucks. Then, some fire trucks drove off. Now there are 4 fire trucks at the station. How many fire trucks drove off?

Write a number sentence to match the story. Use the ? for the unknown number.

How many fire trucks drove off?

fire trucks

ref_doc_title.

Learn with an example

question

Read the story.

There were 17 polar bears on a block of ice. Then, some polar bears swam away. Now there are 10 polar bears on the ice. How many polar bears swam away?

Write a number sentence to match the story. Use the ? for the unknown number.

How many polar bears swam away?

polar bears

solution

There were 17 polar bears on a block of ice. Then, some polar bears swam away. Now there are 10 polar bears on the ice. You need to find how many polar bears swam away. It can be helpful to draw a model.

polar bears to start

polar bears that swam away

polar bears now

You can write a subtraction sentence and find the missing number.

–

Or you can use the related subtraction sentence.

–

7 polar bears swam away.

Looking for more? Try this:

$Confetti$

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Questions
answeredQuestions

Time
elapsedTime

hr	min	sec
00	00	06

SmartScore
out of 100
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X.3Word problems with change unknown - up to 20

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