March 10, 2009 It is not the mountain we conquer but ourselves. ~Edmund Hillary

March 10, 2009 Division & Multiplication wrap-up Review for Exam 2

March 5, 2009 *W deadline: Today Test 2 – Thursday, 3/12 (50 min.) Covers: Text 3.3 & 3.4 (Multiplication and Division) Explorations (3.13, 3.15, 3.18, 3.19, 3.20) Class Notes

3.3 & 3.4 wrap-up If 15 3 = 45, and = 450, and = 45,000, then explain how to find 150,000 3,000. You may not use the words “move the decimal point” or “move the 45.” How might you explain this to a child?

3.3 & 3.4 wrap-up Explain how to find 450,000 ÷ 3,000. You may not use the words “move the decimal point” or “cancel the zeros.” How might you explain this to a child?

3.3 & 3.4 wrap-up Given: 4 7 × __ Question: Without doing any work, what is 30 47? How do you know?

3.3 & 3.4 wrap-up Given: Question: Without doing any work, what is ? How do you know?

3.3 & 3.4 wrap-up Formal Link We know that multiplication and division are inverses. Another way to think about their relationship: (if the divisor is not equal to 0) dividend ÷ divisor = quotient with remainder means the same as quotient divisor + remainder = dividend.

3.3 & 3.4 wrap-up Check this: 35 ÷ 4 = 8 R 3 means the same as = 35 You try this for 147 ÷ 15.

3.3 & 3.4 wrap-up Order of operations Make this equation true, using parentheses: 12 ÷ 4  2 5 = 30 What other values can we get using 12 ÷ 4  2 5?

3.3 & 3.4 review Scaffolding example (some of you had some trouble):

Homework Prepare for Thursday’s exam. You may use a calculator and/or your own manipulatives pack.