Slide 1Homework CommentsSlide 3Can you…Slide 5Slide 6Slide 7Slide 8Slide 9Slide 1027984 ÷ 82Slide 12Do I Understand???Do I Understand?Make this true for order of operationsHomework CommentsCan you…•Show why x •0=k is not true for nonzero x?Explain what is wrong:“50 ÷ 7 is the same as 50 ÷ 10, (which is 5) then because I adding 3 to the divisor I now need to subtract 3: 5 - 3 = 2.”•Estimate 35 • 49.•Show 3 different ways to find:35 • 49.•Estimate 27984 ÷ 82. •Show 27984 ÷ 82 using the scaffolding method.•35 • 49 is about 35 • 50. •Think: 30 • 50 = 1500, and 5 • 50 = 250, so 1750.•Methods: rectangular area, lattice multiplication, Egyptian Duplation, any of the methods used by the kids.•27984 ÷ 82: 82 • 1 = 82; 82 • 10 = 820; 82 • 100 = 8,200; 82 • 1000 = 82,000.So, the quotient is between 100 and 1000, and is closer to 100. Now: 8 • 3 = 24, so guess 300.27984 ÷ 82•82 • 1 = 82; 82 • 10 = 820; 82 • 100 = 8,20082 ) 27984 24600 3384 1640 1744 1640 104 82 22 1 20 20 300I’m thinking of a number. It is less than 50. When I divide it by 8, I get a remainder of 5. But when I divide it by 7, I get a remainder of 2. Use the manipulatives to find my number.Do I Understand???•Given: 4 7X 3 9 4 2 3 1 4 1__ 1 8 3 3•Question: Without doing any work, what is 30 • 47? How do you know?Do I Understand?•Given: 208 R 718 ) 3751 36151144•Question: Without doing any work, what is 200 • 18? How do you know?Make this true for order of operations12 ÷ 4 - 2 • 5 = 30What other values can we get using 12 ÷ 4 - 2 •
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