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Lesson 2 Homework Review
1.
· For every 16 tiles, there are 4 white tiles
· The number of black tiles to the number of white tiles is 2:4.
· The number of gray tiles to the number of white tiles is 10:4.
· There are twice as many white tiles as black tiles.
· For each black tile there are two white tiles.
· The ratio of black tiles to bathroom tiles is 2 to 16.
2. The numbers in the ratio were written in the wrong order. He
wrote the ratio of trucks to cars. The ratio of cars to trucks is 3:1.
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Module 1
Ratios and Unit Rates
Topic A: Representing and Reasoning About Ratios
Lesson 3: Equivalent Ratios
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Exercise 1
Write a one‐sentence story problem (ratio relationship) about a ratio.
Write the ratio in two different forms.
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Exercise 2
Shanni and Mel are using ribbon to decorate a project in their art class. The ratio of the length
of Shanni’s ribbon to the length of Mel’s ribbon is 7: 3.
Let’s represent this ratio in a table.
We can use a tape diagram to represent the ratio of the lengths of ribbon.
Let’s create one together.
· How many units should we draw for Shanni’s portion of the ratio?
· How many units should we draw for Mel’s portion of the ratio?
Draw a tape diagram to represent this ratio:
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What does each unit on the tape diagram represent?_________________
What if each unit on the tape diagrams represents 1 inch? What are the lengths of the ribbons?
Shanni _______________ Mel ____________
What is the ratio of the lengths of the ribbons? _______________
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What if each unit on the tape diagrams represents 2 meters?
What are the lengths of the ribbons?
Shanni _______________ Mel ____________
How did you find that?
What is the ratio of the length of Shanni’s ribbon to the length of Mel’s ribbon now? ________
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What if each unit represents 3 inches? What are the lengths of the ribbons?
Shanni _______________ Mel ____________
If each of the units represents 3 inches, what is the ratio of the length of Shanni’s ribbon to the
length of Mel’s ribbon?______________
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We just explored three different possibilities for the length of the ribbon; did the number of
units in our tape diagrams ever change?
What did these 3 ratios, 7:3, 14:6, 21:9, all have in common?
Mathematicians call these ratios equivalent. What ratios can we say are equivalent to 7:3?
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Exercise 3
Mason and Laney ran laps to train for the long‐distance running team. The ratio of the number
of laps Mason ran to the number of laps Laney ran was 2 to 3.
a. If Mason ran 4 miles, how far did Laney run? Draw a tape diagram to demonstrate how you
found the answer.
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b. If Laney ran 930 meters, how far did Mason run? Draw a tape diagram to determine how you found the
answer.
c. What ratios can we say are equivalent to 2:3?
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Josie took a long multiple‐choice, end‐of‐year vocabulary test. The ratio of the number of
problems Josie got incorrect to the number of problems she got correct is 2:9.
a. If Josie missed 8 questions, how many did she get right? Draw a tape diagram to
demonstrate how you found the answer.
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b. If Josie missed 20 questions, how many did she get right? Draw a tape diagram to
demonstrate how you found the answer.
c. What ratios can we say are equivalent to 2:9?
2:9 8:36
A:B C:D
A· 4 = C
B · 4 = D
4 is the constant(c)
2:9 20:90
A:B C:D
A· 10 = C
B · 10 = D
10 is the constant(c)
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d. Come up with another possible ratio of the number Josie got wrong to the number she got
right.
e. How did you find the numbers?
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f. Describe how to create equivalent ratios.
g. Are the two ratios you determined equivalent? Explain why or why not.
2:9, 8:36, 20:90 are equivalent because they represent the same value. The
diagrams never changed, only the value of each unit in the diagram.
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Closing
Please take out your exit ticket for Lesson 1, close your
binder, and complete the exit ticket. This will be collected.
