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Introduction to proportional relationships

Proportional relationships are relationships between two variables where their ratios are equivalent. Another way to think about them is that, in a proportional relationship, one variable is always a constant value times the other. That constant is known as the "constant of proportionality".

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• i need more help with this, i don't understand
• Well, a proportional relationship means that the ratio between two variables stayed the same.
Eg.
4 eggs = 2 cups of milk
8 eggs = 4 cups of milk
30 eggs = 15 cups of milk
As you can see, this is a proportional relationship because the ratio between the number of egg and cup of milk is 2:1 through out the table.

A non-proportional relationship os when the two variables have different ratio
Eg.
4 eggs = 4 cups of milk
5 eggs = 6 cups of milk
13 eggs = 12 cups of milk
This is not a proportional relationship because there is no same ratio in the table.
Hope that help.
• why are the things that you are teaching us easier than the questions that khan academy is asking us?
• Actually, some of these problems, you may find in the Khan Academy curriculum. Sal just explains the question expertly.
• is it just me ...or we are all staring at our screens like ..."ummm..don't get it"?
• Why do teachers force us to do Khan Academy?
• aperently it gives teachers ahead on the leson
• im crying inside
• maths would be so much harder without this
• If you feel math is too hard look at these jokes to lighten you down:

1. Why was the math book sad? Because it had too many proportion-al relationships!
2. How do you make a proportional relationship laugh? You tell it a funny percentage!
3. I used to have a proportional relationship, but then it just didn't measure up.
4. Why did the proportional relationship break up? It couldn't maintain a steady connection.
5. I told my friend a joke about proportional relationships, but he didn't understand it. It just didn't scale well with him.
6. I asked my math teacher for a joke about proportional relationships, and he said, "I can't, I'm not in the right ratio of humor at the moment."
7. My friend tried to make a joke about proportional relationships, but it was a fraction of what I expected.
8. The proportional relationship and the straight line had an argument, but they resolved it fairly.
9. Why did the proportional relationship go to therapy? It needed help finding its balance.
10. I tried to write a joke about proportional relationships, but it just didn't add up.
• Thank you for making me laugh today, these jokes made it a little bit brighter!
• i need help