1 / 18

Understanding Ratios and Proportions: Class Notes and Assignments

In this lesson, students will explore ratios and proportions, focusing on writing ratios as fractions and determining if two ratios are equivalent. We will review different methods of expressing ratios, including using the word "to," colons, and fractions. Students will practice converting ratios into their simplest form and learn how to compare ratios by cross-multiplying. A summary of key concepts and homework assignments will be provided for reinforcement.

allen-kerr
Download Presentation

Understanding Ratios and Proportions: Class Notes and Assignments

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. MJ2 Ch 7.1 - Ratios

  2. Bellwork • Solve each equation • 8 = y 3 • -6 = 2 m 5 • 3 = 5 x 4 8

  3. Assignment Review • Text p. 287 # 1 – 22

  4. Before we begin… • Please take out your notebook and get ready to work…. • We will continue working with fractions by looking at proportional reasoning…more specifically, today we will be looking at ratios and proportions… • Raise your hand if you can tell me what a ratio is…

  5. Objective • Students will write ratios as fractions and determine if two ratios are equivalent

  6. Ratios • A ratio is a comparison of two numbers by division • There are 3 ways to write a ratio • Using the word “to” • Using a colon (:) • As a fraction • Example: 5 meters to 2 meters can be written as follows: • 5 to 2 • 5:2 • 5 2

  7. Ratios • As with fractions ratios can be expressed in simplest form Example: 25 to 10 Can be written as 25 = 5 10 2

  8. Your Turn • In the notes section of your notebook write each ratio and express it as a fraction in simplest form • 9 to 12 • 27 to 15 • 8:56

  9. Ratios with different measures • Sometimes you will be given a ratio with different unit values and asked to write it as a ratio in simplest form • BE CAREFUL HERE! – when writing ratios comparing units of length, time, weight, etc… both measures should be in the same unit… • Students often make a mistake here! • Let’s look at an example…

  10. Example • Write a ratio of 2 feet to 10 inches as a fraction in simplest form. Set up the ratio 2 feet 10 inches Convert the feet to inches 24 inches 10 inches Simplify 12 5

  11. Your Turn • In the notes section of your notebook write the ratios then convert them to a fraction in simplest form. • 4 feet: 4 yards • 15 ounces to 3 pounds • 9 hours to 3 days

  12. Comparing Ratios • Sometimes you will be asked to compare ratios to determine if they are equivalent (equal) to each other • To do so write each ratio as a fraction equal to each other and then cross multiply. • If both sides equal then the ratios are equivalent • Let’s look at an example…

  13. Example • Determine if 6:8 and 36:48 are equivalent Set up the fractions 6 = 36 8 48 Cross multiply 288 = 288 Since 288 is equal to 288 the ratios are equivalent. IMPORTANT! – you can only cross-multiply if there is an equal sign between 2 ratios

  14. Non-Example • Determine if 9:2 and 45:6 are equivalent Set up the fractions 9 = 45 2 6 Cross Multiply 90 ≠ 54 In this instance 90 does not equal 54 so the ratios are not equivalent

  15. Your Turn • In the notes section of your notebook write each ratio and determine if they are equivalent. • 3 and 6 8 12 • 35 students to 5 adults and 14 students to 2 adults

  16. Summary • In the notes section of your notebook summarize the key concepts covered in today’s lesson • Today we discussed • Ratios – what are they? • How do you write a ratio? • How can you tell if ratios are equivalent?

  17. Assignment • Text p. 290 # 14 – 29 • Write the problem and your answer • I do not accept answers only! • This assignment is due tomorrow

More Related