Module 2 Lesson 16 Objective Use divide by

Module 2 Lesson 16 Objective: Use divide by 10 patterns for multi-digit whole number division.

Fluency – Sprint: Divide by Multiples of 10 and 100 3 ÷ 10 = ____ 43 � 430 ÷ 10 = ___ � 3, 600 ÷ 300 = 12 __ � 1, 290 ÷ 30 = 43 ___ � 18, 400 ÷ 80 = 230 __ 9 � 900 ÷ 100 = ____ 85 � 850 ÷ 10 = ____ � 12, 800 ÷ 200 = 64 _ � 3, 000 ÷ 300 = 10 ___ � 30 480 ÷ 40 = 12 ___ 12 36 ÷ 3 = ____ 1, 290 ÷ 3 = 430 ___ 600 ÷ 300 = 2___ 18, 400 ÷ 800 = 23 _ 300 900 ÷ 9 = ____ 8, 500 ÷ 100 = 85 __ 300 ÷ 100 = 3___ 2, 000 ÷ 20 = 100 ___ 9, 600 ÷ 3 = 3, 200 ___ 3, 600 ÷ 100 = 12 __ 129 1, 290 ÷ 10 = ___ 600 ÷ 30 = 20 ____ 900 ÷ 10 = ____ 90 900 ÷ 90 = 10 ____ 1, 280 ÷ 20 = 64 __ 3, 000 ÷ 100 = 30 __ 2, 000 ÷ 200 = 10 __

Fluency – Group Count by Multiples of 10 � Count by threes up to 60 (as a class). � 3, 6, 9. 12. 15, 18, 21, 27, 30, 33, 36, 39, 42, 45, 48, 51, 54, 57, 60 � Count by 3 tens up to 30 tens (as a class). � 3 tens, 6 tens, 9 tens, 12 tens, 15 tens, 18 tens, 21 tens, 24 tens, 27 tens, 30 tens � How do you say 9 tens in standard form? � 90 � How do you say 12 tens in standard form? � 120 � How do you say 210 tens in standard form? � 2, 100

Application Problem � The area of a vegetable garden is 200 ft 2. The width is 10 ft. What’s the length of the vegetable garden? Draw a picture to help visualize garden. 10 ft. 200 ft 2 ÷ 10 = 20 ___ ft Hint: Think 10 x ? = 200 ? ft.

Concept Development – Problem 1 � � 420 ÷ 10 How would this number be written in unit form based on hundred(s) and ten(s)? � � � 4 hundreds 2 tens. Using number disk show 420 using number disk. Think of the disk in unit form. 100 100 10 10 ÷ 10 10 � 1 10 1 42 What is 4 hundreds divided by 10 and what is 2 tens divided by 10? � � 1 What is the final answer? � � = 42 What is 10 divided by 10? � � 10 What is 100 divided by 10? � � 10 10 4 tens and 2 ones What is this in standard form? � 42

Concept Development – Problem 2 � � � 1, 600 ÷ 100 Work with a partner to solve. Partner A will use number disks to solve, and Partner B will use the place value mat to solve. What did your solutions look like? � � What is the final answer to 1, 600 ÷ 100? � � 16 hundreds divided by 1 hundred equals 16 Why did we change from hundreds to ones in our quotation? � � Division equation. Read the division equation in unit form? � � The digits will all move two places to the right. What term could we use besides division sentence? � � 16 hundreds and 1 hundred What will happen to the digits in 1, 600 when we divide by 100? � � 16 Now let’s try to solve this problem using our knowledge of place value. What is 1, 600 and 100 in unit form? � � Sample work on board. 1 hundred divided by 1 hundred is just 1. What is 16 hundreds ÷ 1 hundred? � 16

Concept Development – Problem 3 � 24, 000 ÷ 600 = 40 � How is this different from the previous problems? � The divisor is a multiple of 10 or 100 where as the other divisors were 10 or 100. � Can � Yes, because you can do 6 x 100. � How � 600 be decomposed with a factor 0 f 100? Why or why not? could the problem be rewritten? 24, 000 ÷ 100 ÷ 6 � What � is the quotient of 24, 000 ÷ 100? 240 � Now we need to divide the above quotient by 6 to finish the problem. � What is 240 ÷ 6? � 40

Concept Development – Problem 4 - 7 � 180, 000 ÷ 9, 000 = � What could the problem be by decomposing 9, 000? � 180, 000 � What � 180 ÷ 1, 000 ÷ 9 is the quotient to the above problem? ÷ 9 = 20 � Another way to look at problems like this is to cross off a zero on each side until there are no more zeros. � 180, 000 � Solve ÷ 9, 000 = 180 ÷ 9 = 20 the following problems: ÷ 30 = 700 � 45, 000 ÷ 5, 000= 5, 000 � 2, 500 ÷ 50 = 50 � 21, 000

End of Lesson Activities � Student Debrief � Problem Set � Exit Ticket � Homework

Problem Set � Divide. Draw disks to show your thinking for a and c. You may use disk for the other problems or just show you are decomposing the problems. � a) 500 ÷ 10 b) 360 ÷ 10 c) 12, 000 ÷ 100 � d) 450, 000 ÷ 100 e) 700, 000 ÷ 1, 000 f) 530, 000 ÷ 100 � Divide. The first one is done for you. Follow the example. � 12, 000 ÷ 30 = 12, 000 ÷ 10 ÷ 3 = 1, 200 ÷ 3 =400 12, 000 ÷ 3, 000 560, 000 ÷ 700 560, 000 ÷ 7, 000 28, 000 ÷ 40 450, 000 ÷ 500 810, 000 ÷ 9, 000 The floor of a rectangle banquet hall has an area of 3, 600 m 2. The length is 90 m. � � � What is the width of the banquet hall? A square hall has the same area. What is its length? A third rectangle banquet hall has a perimeter of 3, 600 m 2. What is the width if the length is 5 times the width?

Problem Set � Two fifth graders solved 400, 000 divided by 800. Carter said the answer is 500, while Kim said the answer is 5, 000. � Who has the correct answer? Explain your thinking. � What if the problem is 4, 000 divided by 8, 000? What is the quotient?

Exit Ticket � Divide. � 17, 000 Show your thinking. ÷ 100 � 59, 000 ÷ 1, 000 � 12, 000 ÷ 40 � 480, 000 ÷ 600

Homework � Divide. Draw number disk to show your thinking for a and c. You may draw disk for the other problems or show your thinking. � � � a)300 ÷ 10 d)730, 000 ÷ 100 b) 450 ÷ 10 e)900, 000 ÷ 1, 000 c)18. 000 ÷ 100 f)680, 000 ÷ 1, 000 Divide. The first one is done for you. 18, 000 ÷ 20 = 18, 000 ÷ 10 ÷ 2 = 1, 800 ÷ 2 = 900 18, 000 ÷ 2, 000 420, 000 ÷ 600 450, 000 ÷ 9, 000 24, 000 ÷ 30 560, 000 ÷ 700 A stadium holds 50, 000 people. The stadium is divided into 250 different seating sections. How many seats are in each section? Over the course of a year, a tractor-trailer commutes 160, 000 miles across America. � � Assuming a trucker changes his tires every 40, 00 miles, and that he starts with a brand new set of tires, how many sets of tires will he use in a year? If the trucker changes the oil every 10, 000 miles and he starts the year with a fresh oil change, how many times will he change the oil in a year?