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## 7th grade

### Unit 4: Lesson 4

Identifying proportional relationships- Intro to proportional relationships
- Proportional relationships: movie tickets
- Proportional relationships: bananas
- Proportional relationships: spaghetti
- Identify proportional relationships
- Proportional relationships
- Proportional relationships
- Is side length & area proportional?
- Is side length & perimeter proportional?

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# Proportional relationships: spaghetti

Given a table of ratios, watch as we test them for equivalence and determine whether the relationship is proportional. Created by Sal Khan.

## Want to join the conversation?

- what do you do to find the answer(12 votes)
- Find the relationship between two variable.(0 votes)

- Who taught you to make spaghetti? Papyrus from Undertale?(12 votes)
- its not allowing me to watch the video(4 votes)
- Try refreshing and if it doesn't work you can read the transcript.(5 votes)

- its said like this: Bowl-in-yays. its yays.(5 votes)
- can i do this without math(2 votes)
- This is a math problem, so you will have to do some math.(6 votes)

- I don't understand this question. A proportional relationship happens when the ratios that are formed are equal so you have to do the operation by the same number for example if I were multiplying by 2, I would multiply all of the numbers by 2. But in this example, 2 of the pairs were divided by 3 and one was divided by 5. So how come this works?(2 votes)
- You wouldn't need to multiply by the same number, because as long as the ratio is equal, they are proportional. In this example, the ratios for all three pairs is 3:5. As another example, 1/2 is proportional to 5/10 and 7/14. Even though you divide by a different factor, you will always get the same ratio of 1 to 2. Hope this helps!(4 votes)

- i do not understand this. do you?(2 votes)
- Well I haven't seen the video yet so I don't know.But if you don't understand just watch the video again and listen carefully or ask question's I hope this helps :)(1 vote)

- There is one thing I don't understand, why divde all the numbers by two different numbers(5,3)? Thank you!(2 votes)
- Stop upvoting your own comments you guys are weird(1 vote)
- it is impossible to upvote/downvote your own comments(3 votes)

- How do you find proportional relationships(2 votes)

## Video transcript

The following table
describes the relationship between the number of
servings of spaghetti bolognese-- I don't know
if I'm pronouncing that-- or bolognese, and the
number of tomatoes needed to prepare them. Test the ratios for
equivalents, and determine whether the relationship
is proportional. Well, you have a
proportional relationship between the number of servings
and the number of tomatoes is if the ratio of
the number of servings to the number of tomatoes
is always the same. Or if the ratio of
the number of tomatoes to the number of servings
is always the same. So let's just think about the
ratio of the number of tomatoes to the number of servings. So it's 10 to 6, which is
the same thing as 5 to 3. So here the ratio is 5 to 3. 15 to 9, if you divide both
of these by 3, you get 5 to 3. So it's the same ratio. 15 to 25, if you divide both
of these by 5, you get 5 to 3. So based on this data,
it looks like the ratio between the number of tomatoes
and the number of servings is always constant. So yes, this relationship
is proportional.