Get ready for 8th grade
- 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?
Given a table of ratios, watch as we test them for equivalence and determine whether the relationship is proportional. Created by Sal Khan.
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- what do you do to find the answer(13 votes)
- its not allowing me to watch the video(4 votes)
- can i do this without math(2 votes)
- That was the quickest video I have ever seen on Khan academy so far!
But I did watch it on x1.5 so.... that did make it go faster. I am in a rush to get 30 minutes by the end of the week for an assignment and my teacher hasn't posted anything new so I am speed-watching old stuff for review. I also have a bunch of tests on Friday and Thursday so I'm trying to study more by doing this quicker. It still helps, but I know all of this anyway. I am learning similar figures right now.(4 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)
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.