How to find an unknown using a known fact

In this lesson, we will use a ratio chart with missing numbers and work out what numbers are missing. We will use the relationships and what we know about adjacent numbers and the facts in our two times table to work out the missing numbers. Resources provided by NCETM (CC BY-NC-SA:


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Lesson summary: How to find an unknown using a known fact

Time to move!

Did you know that exercise helps your concentration and ability to learn?

For 5 mins...

Move around:
Climb stairs

On the spot:
Chair yoga