lesson 16: i can use divide by 10 patterns for multi-digit whole number division 5th grade module 2...
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5th Grade Module 2 – Lesson 16
Lesson 16: I can use ‘divide by 10’ patterns for multi-digit whole
number division
5th Grade Module 2 – Lesson 16
Time to Sprint!
2.E.8 & 2.E.9
5th Grade Module 2 – Lesson 16
Get Your White Board Ready &Let’s Practice Rounding
32 = ___
Round Each Number to the Nearest Ten
3047 = ___5018 = ___2052 = ___5074 = ___7085 = ___9015 = ___20
5th Grade Module 2 – Lesson 16
Let’s practice skip counting or “group counting”
Count by threes and stop at 30.
Now let’s count by 3 tens.Stop when I raise my hand.
STOPSay 9 tens in
standard form
3 tens…
3, 6, 9, 12, 15, 18, 21, 24, 27, 30
GO!Keep on group
counting by3 tens…
5th Grade Module 2 – Lesson 16
Application Problem
The area of a vegetable garden is 200 ft2. The width is 10 ft. What’s the length of the vegetable garden?
Solution on next slide…
5th Grade Module 2 – Lesson 16
Solution
5th Grade Module 2 – Lesson 16
Concept Development
420 ÷ 10Let’s use number disks to solve this problem. Draw 420 on your white board using number disks.
100
100
100
100
10
10
What is 420 in Unit Form?
Let’s Divide. What is 1 hundred divided by 10?
10So if 1 hundred divided by 10 is 10,What is 4 hundreds divided by 10?
4 tens.Let’s show that division with our number disks.
Draw an arrow showing ÷ 10. Record with me.
What is 1 ten divided by 10?1So if 1 ten divided by 10 is 1 What is 2 tens divided by 10?
2 ones.Let’s show that with number disks. Draw with me.Let’s read the original problem with the solution
420 ÷ 10 = 42
÷ 10
10
10
10
10
1
1
4 hundreds 2 tens420
4 tens 2 ones42÷ 10
5th Grade Module 2 – Lesson 16
420 ÷ 10Let’s solve this problem again using our place value mats
without the disks. Show 420 in numerical form on your mat.
1,000,000millions
100,000hundred
thousands
10,000ten
thousands
1,000thousand
s
100hundreds
10tens
1ones
0.1tenths
0.01hundredths
0.001thousandth
s
4 2 0
When we divide this whole number by 10, will the quotient be greater than or less than 420?
Turn & Talk
If it will be less what direction will the digits shift when we divide by 10? How many places?
So, we will shift to the right one place.Cross out the digits and use arrows to show the shifting of the digits on your place value chart. Check with your
partner when you’re finished.
4 2 0
÷ 10
420 ÷ 10 = 42
5th Grade Module 2 – Lesson 16
1,600 ÷ 100 =Work with your partner to solve this problem.
Solve using your place value chart.What is the solution?
16Let’s try to solve this problem now using our
knowledge of place value.Let’s say 1,600 in unit form.
How many hundreds in 1,600?
1,600 ÷ 100 =16 hundreds
16 hundreds is divided by what?
÷ 1 hundred
Visualize what will happen to the digits in 1,600 when we divide by 100.
Tell your partner what will happen.
What is our complete division equation in unit form?Tell Your Partner
16 hundreds ÷ 1 hundred = 16 ones
Why did our unit change from hundreds to ones?Turn & Talk
5th Grade Module 2 – Lesson 16
24,000 ÷ 600How is this problem different from the others we’ve solved?
Turn & Talk
Our divisor this time is 600. Can we decompose 600 with 100 as a factor?
100 x 6 = 600Let’s rewrite our problem by taking out the 100
24,000 ÷ 600= 24,000 ÷ 100 ÷ 6
What is 24,000 ÷ 100
÷ 6
24,000 ÷ 100 = 240
Are we finished though?
No! We still need to divide by 6.
What is 240 ÷ 6?Solve it on your
white board!
= 40Let’s say the original division equation with the
quotient.
24,000 ÷ 600 = 40
240
5th Grade Module 2 – Lesson 16
180,000 ÷ 9,000How can we re-write this division problem so the 9,000 is
decomposed with 1,000 as a factor?Turn & Write it with your Partner.
180,000 ÷ 1,000 ÷ 9
Work with your partner to solve. If you want, you may use your place value chart to help.
Click for Solution
5th Grade Module 2 – Lesson 16
Get Ready to Complete theProblem Set on Your Own!
Complete Pages 2.E.10 – 2.E.12You will have 15 minutes to work.
Try your Best!
5th Grade Module 2 – Lesson 16
LET’S DEBRIEF• When solving the questions in Problem 1, did you find using
number disks to be helpful? Why or why not?
• Look back at your solutions to Problem 2 (a–f). What pattern did you find? Can you explain the relationship between the quotients?
• How did your knowledge of basic facts help you as you solved the questions in Problem 2?
• Talk with your neighbor about your thought process as you solved Problem 3(b).
5th Grade Module 2 – Lesson 16
LET’S DEBRIEF• Look back at Problem 4. What did you notice about the
correct answer in Kim and Carter’s problem and the quotient in 4(b)? Can you create a similar division problem that would yield the same quotient? What about a problem with a quotient that is 10 times greater? 100 times greater? 1 tenth as large?
• Use Problem 4 to generate a word problem where the quotient (500) represents the number of groups of 400 that can be made from 8,000. Then, generate a situation where the quotient (500) represents the size of each of 400 groups.
5th Grade Module 2 – Lesson 16
EXITTICKETPage 2.E.13