Halving and Doubling 10 questions Lesson # 8 Halving and Doubling 10 questions

Did you know… You can take half of one factor and double the other ?

Without changing the… PRODUCT (Answer)

Watch… 4 x 5 is like 2 x 10

OR… 8 X 5 Is like 4 X 10

So what you do is… Take half of either number (the easiest one to cut in two)

And then… Double the other one!

Then multiply! Example: 4 X 15 … Is like… 2 X 30.

You can even do that a third or fourth time… Watch… 15 X 32… Is like… 30 X 16… Which is also like… 60 X 8 = 480 !

And now for some (10) P R A C T I E

Questions ! Ready? Set… Go!

Question # 1 15 X 4 = ?

Question # 2 6 X 15 = ?

Question # 3 4 X 35 = ?

Question # 4 13 X 8 = ?

Question # 5 16 X 25 = ?

Question # 6 8 X 18 = ?

Question # 7 35 X 12 = ?

Question # 8 8 X 250 = ?

Question # 9 12 X 225 = ?

Question # 10 15 X 32 = ?

And now for the Answers ! Prepare yourself !

Question # 1 15 X 4 = 60

Question # 2 6 X 15 = 90

Question # 3 4 X 35 = 140

Question # 4 13 X 8 = 104

Question # 5 16 X 25 = 400

Question # 6 8 X 18 = 144

Question # 7 35 X 12 = 420

Question # 8 8 X 250 = 2000

Question # 9 12 X 225 = 2700

Question # 10 15 X 32 = 480

The END