Number sentences

Number sentences with an unknown, solved with the inverse operation. Read one part at a time and tap “I know this”. Then test yourself in the quiz.

Your progress0 of 3

A number sentence is a maths sentence with an equals sign: 25 + □ = 40. The □ is the unknown.

Rule

Use the inverse operation: 25 + □ = 40 → □ = 40 − 25 = 15. □ × 6 = 42 → □ = 42 ÷ 6 = 7.

Tap when you could tell someone without looking.

Words become number sentences

“I had some sweets, gave away 8 and now have 15 left.” → □ − 8 = 15 → □ = 23.

Tap when you could tell someone without looking.

Tap when you could tell someone without looking.

Remember this: your summary

Write these points in your book. Read them again the night before the test.

Memory trick

Do the opposite to unlock the box.

Flash cards · Tap to turn over

First say the answer yourself, then turn the card over.

Test yourself · Part 2

Read the question and the answer. Is the answer right? Tap True or False.

Now the real quiz!

The quiz has many more questions on this topic. Every question shows straight away whether you are right and explains why.

For parents

Let your child work the examples on paper and explain them to you.
The ticks (“I know this”) are saved on this device only. We never ask for names or emails.

Follows CAPS for Grade 5 Mathematics. Always check your teacher’s notes and textbook too.