Complete the addition sentence - up to three digits: Example question
30 October 2026
Word problems often ask children to find a missing number in an addition sentence. These questions help your child practise thinking about how numbers fit together to make a total.
Example question
There are 245 red balloons and some blue balloons at the party. There are 378 balloons altogether. How many blue balloons are there?
Step 1: Write the addition sentence with a missing number. 245 + ___ = 378
Step 2: Find the missing number by subtracting 245 from 378. 378 - 245 = 133
Step 3: Complete the addition sentence. 245 + 133 = 378
Answer:
There are 133 blue balloons at the party.
After seeing this example, your child will know how to spot the missing part in an addition sentence with up to three digits. They can now try similar word problems to build their confidence.
