Ratio and proportion in geometry I

In this lesson, you will compare the side lengths of triangles, one of which is an enlargement of the other, and calculate the ratios of the lengths of corresponding sides.

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.Fill in the gap: If two quantities are in the same ratio then there are _______ relationships I can use to find a missing value.

1/5

Q2.Lots of the same groups of yellow and red counters are put in a bag. Fill in the missing value in the ratio table.

2/5

Q3.Lots of the same groups of yellow and red counters are put in a bag. Fill in the missing value in the ratio table.

3/5

Q4.Lots of the same groups of yellow and red counters are put in a bag. Fill in the missing value in the ratio table.

4/5

Q5.Yellow and red counters are in the ratio 2 : 3. What fraction of the counters are yellow?

5/5

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.Fill in the gap: If two quantities are in the same ratio then there are _______ relationships I can use to find a missing value.

1/5

Q2.Lots of the same groups of yellow and red counters are put in a bag. Fill in the missing value in the ratio table.

2/5

Q3.Lots of the same groups of yellow and red counters are put in a bag. Fill in the missing value in the ratio table.

3/5

Q4.Lots of the same groups of yellow and red counters are put in a bag. Fill in the missing value in the ratio table.

4/5

Q5.Yellow and red counters are in the ratio 2 : 3. What fraction of the counters are yellow?

5/5

Video

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Worksheet

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This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Ratio and proportion in geometry (part 1)

Show what you've learned by taking this quiz.

Q1.State the ratio between the side lengths AB and BC.

1/5

Q2.State the constant of proportionality between triangle ABC and triangle DEF.

2/5

Q3.Find the length of side DE.

3/5

Q4.Find the length DE.

4/5

Q5.Find the length DE.

5/5

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Ratio and proportion in geometry (part 1)

Show what you've learned by taking this quiz.

Q1.State the ratio between the side lengths AB and BC.

1/5

Q2.State the constant of proportionality between triangle ABC and triangle DEF.

2/5

Q3.Find the length of side DE.

3/5

Q4.Find the length DE.

4/5

Q5.Find the length DE.

5/5

Lesson summary: Ratio and proportion in geometry I

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