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# Copyright © Mathematics Mastery 2017
Parental Guidance
In this unit, pupils multiply and divide using mental methods and are first introduced to written short methods of multiplication and division. This week, pupils have been using mental methods of multiplication and division.
In Year 3 pupils multiplied and divided using mental methods of calculation.
In Year 5 pupils continue to use both mental and written methods of multiplication and division, extending this to decimal numbers and division with remainders.
Mental strategies for multiplication and division, which pupils have used this week:
Using known facts
30 x 7 = ?
Using the distributive law
16 x 6 = ?
Using the associative law
2 x 7 x 5 = ?
Unit 3: Multiplication and division (Week 1 of 3)
Next Step for Depth
Write out all of the multiples of 11 from 1 × 11 up to 20 × 11.
What patterns do you notice in the numbers? Describe and explain the pattern.
I know 3 x 7 = 21. One of the factors, 30, is ten times bigger than 3. So the product will be ten times bigger too. 30 x 7 = 210.
I know 10 x 6 = 60 and 6 x 6 = 36.
60 + 36 = 96.
16 x 6 = 96.
It doesn’t matter what order I multiply the number in, I’ll still get the same product.
2 x 5 = 10 10 x 7 = 70
or 2 x 7 = 14 14 x 5 = 70
or 7 x 5 = 35 35 x 2 = 70