1 / 17

Adding and Subtracting Meters and Centimeters

Adding and Subtracting Meters and Centimeters. 3B: 6.1c. Adding m & cm with no renaming. 2. 85. 2 m 60 cm + 25 cm = _____ m _____ cm How do you get the answer? Since there are no meters in front of 25 cm, just add the centimeters. Adding m & cm with renaming. 3. 35.

lei
Download Presentation

Adding and Subtracting Meters and Centimeters

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Adding and Subtracting Meters and Centimeters 3B: 6.1c

  2. Adding m & cm with no renaming 2 85 • 2 m 60 cm + 25 cm = _____ m _____ cm • How do you get the answer? • Since there are no meters in front of 25 cm, just add the centimeters.

  3. Adding m & cm with renaming 3 35 • 2 m 60 cm + 75 cm = _____ m _____ cm • You can still add the centimeters since there are no meters in front of the 75 cm. • 60 cm + 75 cm = 135 cm • Can you leave the 135 cm as it is? • Convert it into m and cm. • 1 m 35 cm + 75 cm 2 m 135 cm = 2 m 60 cm 3 m 35 cm

  4. Another way • You could also make 100 with either 60 cm or 75 cm. 75 cm 2 m 60 cm + 35 cm 25 cm 2 m 35 cm 1 m 3 m 35 cm + =

  5. Another way • Now let’s make 100 with the 60. How much do we need from the 75? • How much is left? 75 cm 2 m 60 cm + 40cm 35 cm 2 m 3 m 35 cm 1 m 35 cm + =

  6. One more strategy… • You can add the numbers up vertically. • First, convert into cm. • Add. • Convert back to m and cm. 2m 60 cm 260 cm + 75 cm + 75 cm 3m 35 cm 335 cm

  7. Adding both meters and centimeters • 2 m 65 cm + 3 m 20 cm = _____ m _____cm • Use mental calculation to add the meters. • Then add the centimeters. 2 m 65 cm + 3 m 20 cm 5 m 65 cm + 20 cm 5 m 85 cm

  8. Adding both meters and centimeters • Try this one… • 2 m 65 cm + 3 m 40 cm = _____ m _____cm • Add the meters. • Then add the centimeters and rename. 2 m 65 cm + 3 m 40 cm 5 m 65 cm + 40 cm 5 m 105 cm 6 m 5 cm

  9. Use vertical adding, if you prefer • First, convert into cm. • Add. • Convert back to m and cm. 2 m 65 cm 265 cm +3 m 40 cm + 340 cm 6 m 5 cm 605 cm

  10. Subtracting both meters and centimeters 5 5 • 5 m 30 cm – 25 cm = _____m _____ cm • To find the answer, subtract 25 cm from 30 cm. There are no meters to take away so the 5 m stays the same.

  11. Subtracting both meters and centimeters 4 55 • 5 m 30 cm – 75 cm = _____m _____ cm • Take 100 cm from the 5 meters. What’s left? • Subtract the 75 from the 100. • Add the remaining cm together. 75 cm = 5 m 30 cm – = 4 m 30 cm + 25 cm 4 m 30 cm 100 cm 75 cm – = 4 m 55 cm

  12. Other strategies • Is there another way to solve the problem 5 m 30 cm – 75 cm? • You can rename 5 m 30 cm. • Then subtract. 5 m 30 cm – 75 cm = 4 m 130 cm – 75 cm = 4 m 55 cm

  13. Use vertical subtracting, if you prefer • First, convert into cm. • Subtract. • Convert back to m and cm. 5 m 30 cm 530 cm – 75 cm – 75 cm 4 m 55 cm 455 cm

  14. Subtracting when you don’t have to rename • 5 m 30 cm – 2 m 25 cm = ____ m _____ cm • How should we solve this? • Subtract meters first. • Then subtract centimeters. – 2 m – 25 cm 5 m 30 cm 3 m 30 cm 3 m 5 cm

  15. RENAME CONVERT • How do we find the difference between 5 m 30 cm and 2 m 75 cm? • Let’s look at three subtraction strategies… 5 m 30 cm – 2 m 75 cm = 5 m 30 cm 530 cm – 2 m 75 cm – 275 cm 3 m 30 cm – 75 cm = 255 cm 2 m 55 cm 2 m 130 cm – 75 cm = 2 m 55 cm MAKE 100 2 m 75 cm = 5 m 30 cm – 3 m 30 cm – 75 cm = = 2 m 30 cm + 25 cm 2 m 30 cm 100 cm 75 cm – = 2 m 55 cm

  16. Now you try. • Textbook page 12 • Tasks 14-15 • 14 a) 5m 25cm b) 1m 55cm • 15 a) 9m 32cm b) 3m 79cm • c) 8m 30cm d) 6m 46cm • e) 3m 20cm f) 9m 1cm • g) 6m 15cm h) 5m 24cm • i) 4m 55cm j) 3m 95cm • k) 3m 55cm l) 2m 30cm

  17. Extra practice and/or Homework • WB pages 9-10 • EP 113-114 • Review 1B

More Related