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

Fluency – Round to the Nearest Ten 32 ≈ _____ 47 ≈ _____ 18 ≈ _____ 52 ≈ _____ 74 ≈ _____ 85 ≈ _____ 15 ≈ _____ 176 ≈ ____ 132 ≈ ____ 598 ≈ ____ 30 50 20 50 70 90 20 180 130 600

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 ft2. The width is 10 ft. What’s the length of the vegetable garden? Draw a picture to help visualize garden. 10 ft. 200 ft2 ÷ 10 = ___ ft 20 Hint: Think 10 x ? = 200 ? ft. Note: This problem provides a nice opportunity to quickly address area concepts and division by a power of ten, allowing for smooth transition into the day’s Concept Development. While solving, students should be encouraged to draw a picture of a rectangle to support their work.

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. What is 100 divided by 10? 10 What is 10 divided by 10? 1 What is the final answer? 42 What is 4 hundreds divided by 10 and what is 2 tens divided by 10? 4 tens and 2 ones What is this in standard form? 100 100 100 100 10 10 10 10 ÷ 10 = 42 10 10 1 1

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? Sample work on board. What is the final answer to 1,600 ÷ 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? 16 hundreds and 1 hundred What will happen to the digits in 1,600 when we divide by 100? The digits will all move two places to the right. What term could we use besides division sentence? Division equation. Read the division equation in unit form? 16 hundreds divided by 1 hundred equals 16 Why did we change from hundreds to ones in our quotation? 1 hundred divided by 1 hundred is just 1. What is 16 hundreds ÷ 1 hundred?

Concept Development – Problem 3 24,000 ÷ 600 = 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 600 be decomposed with a factor 0f 100?Why or why not? Yes, because you can do 6 x 100. How 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 40

Concept Development – Problem 4 - 7 180,000 ÷ 9,000 = What could the problem be by decomposing 9,000? 180,000 ÷ 1,000 ÷ 9 What is the quotient to the above problem? 180 ÷ 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 ÷ 9,000 = 180 ÷ 9 = 20 Solve the following problems: 21,000 ÷ 30 = 45,000,000 ÷ 5,000= 2,500 ÷ 50 = 700 5,000 50

End of Lesson Activities Student Debrief Problem Set Exit Ticket Homework

Problem Set Divide. The first one is done for you. Follow the example. Divide. Draw disks to show your thinking for a and c. You may use disk for the other problems or just show how 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. The floor of a rectangle banquet hall has an area of 3,600 m2. 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 m2. What is the width if the length is 5 times the width? 12,000 ÷ 30 = 12,000 ÷ 10 ÷ 3 = 1,200 ÷ 3 =400 12,000 ÷ 300 12,000 ÷ 3,000 560,000 ÷ 70 560,000 ÷ 700 560,000 ÷ 7,000 28,000 ÷ 40 450,000 ÷ 500 810,000 ÷ 9,000

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 4,000,000 divided by 8,000? What is the quotient?

Exit Ticket Divide. Show your thinking. 17,000 ÷ 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 b) 450 ÷ 10 c)18.000 ÷ 100 d)730,000 ÷ 100 e)900,000 ÷ 1,000 f)680,000 ÷ 1,000 Divide. The first one is done for you. 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? 18,000 ÷ 20 = 18,000 ÷ 10 ÷ 2 = 1,800 ÷ 2 = 900 18,000 ÷ 200 18,000 ÷ 2,000 420,000 ÷ 60 420,000 ÷ 600 450,000 ÷ 9,000 24,000 ÷ 30 560,000 ÷ 700