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I can learn about ratios and how to compare them. I can correctly write a ratio three ways. Warm Up 2 Point TCAP: Watch the clock, 10 minutes! Ready…go!!. Vocabulary. Ratio: a comparison of two numbers or quantities. 4/3 4 to 3 4:3. Writing Ratios.
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I can learn about ratios and how to compare them. I can correctly write a ratio three ways. Warm Up 2 Point TCAP: Watch the clock, 10 minutes! Ready…go!!
Vocabulary Ratio: a comparison of two numbers or quantities. 4/3 4 to 3 4:3
Writing Ratios Ratios can be written three ways 1) as a fraction 4/3 2) with the word “to”4 to 3 3) with a colon: 4:3 Write the numbers in the order they appear in the problem. If the first number is larger then the numerator will be larger. That is fine. If the problem says “and” that is your clue to add things being compared.
Writing Ratios Example 1: Part:Part A basket of fruit contains 6 apples, 4 bananas, and 3 oranges. Write each ratio in all 3 forms Bananas to apples Number of bananas = 4 Number of apples 6 4/6, 4 to 6, 4:6
Writing Ratios Example 2: Part:Whole A basket of fruit contains 6 apples, 4 bananas, and 3 oranges. Write each ratio in all 3 forms Oranges to total pieces of fruit Number of oranges = ___3____ = 3 Number of total pieces of fruit 6 + 4 + 3 13 3/13, 3 to 13, 3:13
Explain why you think the ratio 4/3 is not written as a mixed number. The quantities being compared could not be read easily as a mixed number. Mental Math
A basket of fruit contains 6 Apples , 4 Bananas , and 3 Oranges. Write the ratio in all three ways.Bananas and Apples to Oranges • 3/10, 3 to 10, 3:10 • 10/3, 10 to 3, 10:3 • 6/3, 6 to 3, 6:3 • 4/6, 4 to 6, 4:6 • All of the above • None of the above 10
Writing Ratios in Simplest Form Sometimes a ratio can be simplified. To simplify a ratio, first write it in a fraction form and then simplify the fraction. Example: At Franklin middle School, there are 252 students in the sixth grade and 9 sixth-grade teachers. Write the ratio of student to the teachers in simplest form. Students = 252÷ 9 = 28 Teachers 9 ÷ 9 1 The ratio of students to teachers is 28 to 1
Comparing Ratios To compare ratios, write them as fractions with common denominators. Then compare the numerators.
Example: Tell whether the wallet size photo or the portrait size photo has the greater ratio of width to length. Wallet: width (in.) = 3.5 Portrait: width (in.) = 8 = 4 length (in.) 5 length (in.) 10 5 5 Because 4 > 3.5 and the denominators are the same, the portrait size photo has the greater ratio of width to length. Comparing Ratios
Guided Practice • The following questions will let you know how much you have learned today.
A coin bank contains 16 quarters, 12 dimes, and 8 nickels. Write each ration in all three forms. Nickels to quarters • 8/16, 8 to 16, 8:16 • 4/3, 4 to 3, 4:3 • 1/2 , 1 to 2, 1:2 • Both A and C • None of the above
A coin bank contains 16 quarters, 12 dimes, and 8 nickels. Write each ration in all three forms. Nickels and dimes to quarters • 12/16, 12 to 16, 12:16 • 20/16, 20 to 16, 20:16 • 5/4, 5 to 4, 5:4 • None of the above • Both B and C
There are 220 calories in 5 crackers. Write the ratio of calories to crackers in simplest form all three forms.
On a school trip, Bus 1 has 3 teachers and 14 students. Bus 2 has 4 teachers and 28 students. Which bus has the greater ratio of teachers to students? • Bus 1 • Bus 2 • A and B • Where’s Bus 3? • All of the above • None of the above