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Question: please help answer questions 1 2 and 3...

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Please help answer questions 1, 2, and 3 Class Activity 4M Relating Multiplication Problems 1. Kylie has an idea for how to calculate 23 x 23. She says, Twenty times 20 is 400, and 3 times 3 is 9; so 23 x 23 should be 400 plus 9, which s 409 Is Kylies method valid? If not, how could you modify her work to make it correct? Dont Just start over in a different way; Work with Kylies idea. Use the large square below, which consi of 23 rows with 23 small squares in each row, to help you explain your answer. 2. Annie is working on the multiplication problem 19 x 21. She says that 19 x 21 should equal 20 X 20 because 19 is one less than 20 and 21 is one more than 20 This is a wonderful idea, but is Annie correct? If not, use the diagram below to help you explain to Annie why not. There are 20 rows of dots with 21 dots in each row. 3. Mary is working on the multiplication problem 19 x 21. She says that 19 x 21 20 x 21, and 20 x 21 is more than 20 x 20, which she knows is 400. thinks this to help her calculate 19 x 21, but she Mary cant quite figure it out. Discuss Marys idea in detail. Can you make her explanation work?

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