Welcome to this IRSC Adult Education Live Virtual Lesson
-
Upload
rogan-richardson -
Category
Documents
-
view
22 -
download
0
description
Transcript of Welcome to this IRSC Adult Education Live Virtual Lesson
![Page 1: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/1.jpg)
Welcome to this IRSC Adult Education Live Virtual Lesson
Diana Lenartiene, Ed. S. moderator/instructor
![Page 2: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/2.jpg)
Elluminate Meeting/Classroom 2
Introducing… your virtual classroom
6/10/2008; updated: 10/3/11
![Page 3: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/3.jpg)
Emoticons Respond to poll
Chat
Adjust volume
![Page 4: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/4.jpg)
6/10/2008; updated: 10/3/11 Elluminate Meeting/Classroom 4
![Page 5: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/5.jpg)
6/10/2008; updated: 8/4/2009 Elluminate Meeting/Classroom 5
![Page 6: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/6.jpg)
6/10/2008; updated: 8/4/2009 Elluminate Meeting/Classroom 6
![Page 7: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/7.jpg)
Adding and Subtracting Decimals
Solve problems involving addition and subtraction of decimals.
![Page 8: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/8.jpg)
![Page 9: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/9.jpg)
To add decimals
Line up the decimal points and add the columns from right to left.
Place a decimal point in the answer directly below the other decimal points.
![Page 10: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/10.jpg)
Example 1
0.64 + 0.39Line up the decimal points.
0.64 + 0.39 __________________________
Add the columns. 0.64
+ 0.39 __________________________
1.03
![Page 11: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/11.jpg)
Example 2
5.74 + 3.3Line up the decimal points. 5.74 + 3.3 _____________________________
Add the columns. 5.74 + 3.3 _____________________________
9.04
![Page 12: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/12.jpg)
Try this one on your own!
39.66
+22.7
Remember, line up the decimals, Place the decimal point in the answer under the ones in the problem,Add like whole numbers.
![Page 13: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/13.jpg)
11
39.66+22.7 62.36
![Page 14: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/14.jpg)
To subtract decimals
Line up the decimal points.Subtract the columns from right to left,
regrouping if necessary.Place a decimal point in the answer
directly below the other decimal points.
![Page 15: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/15.jpg)
Example 10.86 – 0.49
Line up the decimal points0.86
- 0.49 __________________________
Regroup the tenths. Subtract the columns.
0.86 - 0.49 __________________________
167
0.37
![Page 16: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/16.jpg)
![Page 17: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/17.jpg)
NOTE BOOK
You can use graph paper to model decimal multiplication. Here is a model of the product of 0.7 and 0.3.
1
1
0.3
0.7
Because 21 of the 100 squares are shaded, 0.7 0.3
Words
Numbers
Multiplying Decimals
= 0.21.
Multiply decimals as you would whole numbers. Then place the decimal point in the product. The number of decimal places in the product is equal to the sum of the number of decimal places in the factors.
0.7 0.3 = 0.21
Multiplying Decimals
![Page 18: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/18.jpg)
EXAMPLE 1 Multiplying Decimals
Multiplying Decimals
5.82
0.41
2 decimal places
2 decimal places
5 8 22 3 2 8
4 decimal places
–––+––––––
2.3 8 6 2–––––––
1234
![Page 19: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/19.jpg)
Checking Reasonableness To check that the product in Example 1 is reasonable, round each factor to the place value of the leading digit, then multiply. The leading digit of a number is the first nonzero digit.
Multiplying Decimals
5.82 6
0.41 0.4
Round to the nearest whole number.
Round to the nearest tenth.
Because 6 0.4 = 2.4, the product of the previous example is reasonable.
![Page 20: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/20.jpg)
6.45
18
2 decimal places
0 decimal places
5160645
––––––116.10
Because 6 20 = 120, the product is reasonable.
EXAMPLE 2 Multiplying Decimals
–––+––––––
After you place the decimal point, you can drop any zeros at the end of an answer.
2 decimal places
CHECK
Multiplying Decimals
ANSWER 6.45 18 = 116.1
![Page 21: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/21.jpg)
Write a zero before the 7 as a placeholder so that the number has 5 decimal places.
6.45
18
2 decimal places
0 decimal places
5160645
––––––116.10
Because 6 20 = 120, the product is reasonable.
1.273
0.06
3 decimal places
2 decimal places
76380.0 5 decimal places
Because 1 0.06 = 0.06, the product is reasonable.
EXAMPLE 2 Multiplying Decimals
–––+–––––– ––––––– –––+
After you place the decimal point, you can drop any zeros at the end of an answer.
2 decimal places
CHECK CHECK
Multiplying Decimals
ANSWER 6.45 18 = 116.1 ANSWER 1.273 0.06 = 0.07638
![Page 22: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/22.jpg)
Central Park Central Park is a rectangular park about 2.5 miles long and about 0.5 mile wide. What is the area of Central Park?
EXAMPLE 3 Multiplying Decimals to Find Area
SOLUTION
Multiplying Decimals
= l w2.5(0.5)
A = l w
Substitute 2.5 for l and 0.5 for w.
= 1.25
Write formula for area of a rectangle.
ANSWER The area of Central Park is about 1.25 square miles.
Multiply.
![Page 23: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/23.jpg)
Now, you need to make a copy of this screen to send to your teacher for proof ofAttendance. This can be done in three easy steps:
![Page 24: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/24.jpg)
![Page 25: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/25.jpg)
![Page 26: Welcome to this IRSC Adult Education Live Virtual Lesson](https://reader035.fdocuments.in/reader035/viewer/2022062721/5681373f550346895d9ed3af/html5/thumbnails/26.jpg)
Thank you for viewing this presentation.Diana Lenartiene, IRSC ABE Instructor
If you still have questions, please contact me at: