Math - Ratios

Do You Know? What is a ratio? Answer the following question: What is the ratio of boys to girls in this class? Compare your answer with someone sitting around you. Do you need to change your answer from earlier?

What Are You Learning? I CAN find ratios

Why Do You Need To Know This? Ratios are important because they are used to compare different quantities. Ratios are can be used in a variety of ways and can be found many places in the real world. Can you think of any comparisons that can be made in the real world?

Vocabulary Ratio—a comparison of two quantities by division. 2 to 3 2:3 2/3 Equivalent Ratios—two ratios that have the same value. You must simplify two ratios to determine if they have the same value. 2/3 and 4/6 are equivalent because 4/6 will simplify to 2/3

Notes If a ratio is represented as an improper fraction you must leave it as an improper fraction! Example: The ratio 32/12 represented as a fraction simplifies to 8/3

Response Number Have a Job 40 Don’t Have a Job 60 Total 100 Students were asked in a survey whether they had after-school jobs. Write each ratio as a fraction in simplest form. students with jobs to students without jobs students without jobs to all students surveyed students with jobs to all students surveyed students without jobs to students with jobs all students surveyed to students without jobs Response Number Have a Job 40 Don’t Have a Job 60 Total 100

Write each ratio as a fraction in simplest form. 25 to 10 6:18 9 to 12 27:15 8 to 56 30 to 9

Determine whether the two ratios are equivalent. 6:8 and 36:48 3/8 and 6/12 35 students:5 adults and 14 students:2 adults 12:15 and 32:40

You are going to complete a group activity using ratios. Group Work You are going to complete a group activity using ratios.