Unit 5 – Multiplication and division
Let’s try 23 × 5. What is a useful estimate? Look at what happens when 3 ones are multiplied by 5.
3
H T 2
O 3 5
×
1 1 1 1 1 1 1 1 10 10 10 10 10 10 10 10 1 1 1 10 10 1 1 1 1
3 ones multiplied by 5 and then 2 tens multiplied by 5
H
T 2
O 3 5 5
15 ones is 1 ten and 5 more ones
×
10 tens plus 1 more ten is 11 tens or 1 hundred and 1 more ten
1
1 1
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04/05/2022 15:50
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