Musical Chairs! Change your table groups. One person may remain at each table. The remaining students move to another table—each going to a different new table. All tables should have groups that have no more than one person from a previous group.

What’s wrong? is 50, so do 50 12, which is 600, and then subtract 1, and get 599.

Multiplication and Division In mathematics, we say that addition and subtraction are inverse operations. This is why there are related facts: = = = 4 In this same way, multiplication and division are inverse operations: 3 4 = ÷ 4 = 3 12 ÷ 3 = 4

Exploration 3.15 Each person make up a story problem for 15 ÷ 3. Share them with your group. Sort them into two or more piles. Select one from each pile, and read it to the class.

Different Word Problems In any division problem: Dividend ÷ Divisor = Quotient. In word problems, we usually have a rate as part of the problem (apples per person). Where the rate appears determines the type of word problem.

Models for Division Carlos has 24 apples. If it takes 4 apples per pie, how many pies can he make? This is repeated subtraction. Carlos has 24 apples. If he wants to make 4 pies, how many apples will be in each pie? This is partitioning.

Missing Factor Model of Division 28 ÷ 4 = Can be thought of as 4 X ? = 28

Terminology b ÷ n = a iff a∙n = b b is the dividend n is the divisor a is the quotient a and n are the factors of b and b is a multiple of a and n.

The number line! We use the number line with multiplication when we think about continuous models, or multiplication as repeated addition. We can use the number line here to show division as repeated subtraction.

What Properties Hold for Division?

Dividing by Zero

No calculators! Do the following division problem 159 ÷ 13

Division Can you divide without using the Long Division Algorithm? Hint: the answer is YES! Let’s see what students do.

Strategies Amelinda and Alosha both used repeated subtraction. Elaine and Thomas used a combination of repeated subtraction and something else. Describe this.

For this weekend You will finish pages in your packet. This will count as a project grade, not a homework grade--there are 41 total questions that need to be answered. A total of 40 points. For each question, be sure to explain both how the student answered the question, and why the mathematics is appropriate. The length of the answer is not what will get you a good grade!!!