Transcript Document
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Ratios and Vocabulary Lesson 2
Warm Up
OBJECTIVE: Students will use ratio language to describe a relationship between two quantities.
Write a ratio in three ways comparing # of ducks to # of pigs. Remember to simplify your answer!
2 ducks to 1 pig 2 2 ducks : 1 pig
Fill in the blank.
For every 2 ducks, there is____ pig.
Warm Up
OBJECTIVE: Students will use ratio language to describe a relationship between two quantities.
Write a ratio in three ways comparing # of ducks to # of pigs. Remember to simplify your answer!
2 ducks to 1 pig 3 2 ducks : 1 pig
Fill in the blank.
For every 2 ducks, there is____ pig.
1) a fraction 2) the word, “to” 3) a colon :
Agenda:
OBJECTIVE: Students will use ratio language to describe a relationship between two quantities.
If the World Was a Village Video (Independent)
Follow-up Questions (Partner Work)
3) Explore
Mini Lesson (Whole Class and Partner Work)
4) Practice – (Partner Work, Whole Class)
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Launch
We will practice writing ratios by watching a video on the world. Turn and Talk:
What country were you born in?
What languages do you speak? Be ready to share with class!
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Launch
We will practice writing ratios by watching a video on the world. This video pretends that there is a village of 100 people who equally represent every country and language in the world. Watch the “If the World Were a Village Video” and answer questions #1-14.
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Launch Continued
Please check your answers!
Mini Lesson Let’s answer this question together: How can we write a ratio using words?
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(ex ) For every 100 people in the village, there are 61 people from China.
SUPER
important term for writing ratios “
For every
” can be used to replace the fraction bar, colon : or word “to” in a ratio “
For each
” can also be used to replace the fraction bar, colon : or word “to” in a ratio
Explore
For every and for each can be used to replace the fraction bar, colon : or word “to” in a ratio
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Step 1: Write a ratio of beaks to wings 1 beak: 2 wings Step 2: Write this ratio in words An eagle has We can also say, An eagle has 2 wings for each beak.
We use for each when we only have the end?
word plural.
Explore
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We can also start sentences with for every, let’s try!
(ex 2) In a class election, Juan received 20 votes and Kevin received 8 votes. Write a ratio in words comparing Juan and Kevin’s votes.
Step 1: Write a ratio of Juan’s votes to Kevin’s votes 20 Juan’s votes to 8 Kevin’s votes Step 2: Simplify the ratio 5 Juan’s votes to 2 Kevin’s votes Step 3: Write this ratio in words For every, 5 votes that Juan received Kevin received 2 votes.
Yes! 20 to 8 simplify the ratio?
Let’s add a equal fractions!
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Explore – Try with a Partner
(ex 3) Kaylee buys 2 posters that are the same size. She wants to hang up each poster using the following push pins. Write a sentence using for each to answer the question.
How many push pins should she use for each poster?
Step 1: Write a ratio of push pins to posters
8 push pins : 2 posters
Step 2: Simplify the ratio
4 push pins : 1 poster
Step 3: Write this ratio in words
Kaylee needs 4 push pins for each poster.
For each, poster, Kaylee needs 4 push pins.
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Challenge – Try with a Partner
(ex 4) Brian also wants to decorate his room. He has 6 posters that need the same ratio of push pins as Kaylee’s Posters.
How many push pins does Brian need to hang up his posters? - Draw a picture and explain your steps!
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Challenge – Try with a Partner
(ex 4) Brian also wants to decorate his room. He has 6 posters that need the same ratio of push pins as Kaylee’s Posters.
How many push pins does Brian need to hang up his posters? - Draw a picture and explain your steps!
Explanation: Since we have 4 posters and each poster needs 4 push pins, we know that Brian needs at total of
16 push pins.
Fancy Algebra Way:
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Practice
You have 5 minutes to work with your partners on this class work, good luck!
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Practice - Answers
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Summary
We can use the phrase, for every, to help us write ratios as sentences!
Turn and Talk: (ex) Calvin told his friend that his cat has 2 tails for every 1 ear. Is he right? Why or why not? Calvin is wrong. He should have said that his cat has 2 ears for every 1 tail. If Calvin was right then he has a cat with 1 ear and 2 tails, ek!
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Assessment
For #1 and #2, fill in the blanks:
1) We can write ratios as sentences using the phrase, _______ _________ . 2) A human being has ____ fingers for every _____ nose.
3) A brownie recipe calls for 3 cups of white sugar, 2 cups of brown sugar and 1 cup of flour. Write a sentence comparing
cups of flour to cups of brown sugar. 1 cup of flour: 2 cups of brown sugar A brownie recipe has 1 cup of flour for every 2 cups of brown sugar.