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India
Class V

Multiplication x8

Lesson

Sometimes people find times tables tricky and that's ok. Sometimes they just don't know that there are special relationships between certain numbers that can help us solve multiplication questions more easily. We are going to look at a special relationship between the 2, 4 and 8 multiplication tables and how we can use doubling to work out multiplication questions with these numbers.

SINCE THIS STRATEGY USES DOUBLING (THAT IS MULTIPLYING BY 2), MAKE SURE YOU PRACTICE AND FEEL CONFIDENT WITH DOUBLING/ MULTIPLYING BY 2.

Now watch this strategy in action by watching this video!

 

Discussion

1) What is the relationship between the $2$2, $4$4 and $8$8 multiplication tables?

2) How was doubling used to these solve questions in the $8$8 times tables?

 

 

Now see if you answers matched ours!

  • "Multiply by $2$2" means "double the number."
  • "Multiply by $4$4" means "double the number, then double that answer."
  • "Multiply by $8$8" means "double the number, then double that answer, then double that answer again."

 

 

Worked Examples

Question 1

$8\times5$8×5

 

Question 2

$8\times12$8×12

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