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Lesson 9: Analyzing relationships between variables

# Writing equations for relationships between quantities

In this lesson, we learn how to write equations representing real-world scenarios. First, we explore how to calculate time taken for a walk based on speed and distance. Then, we discover how to determine the amount of water needed in a soup recipe based on the quantity of vegetable stock. Fun, right? Created by Sal Khan.

## Want to join the conversation?

• hi how can two variables relate to each other pls make it easy
• Hi "pls sub to adrain not pro g..."
Fundamentally, it means that the values of variable correspond to the values of another variable, for each case in the dataset. In other words, knowing the value of one variable, for a given case, helps you to predict the value of the other one
-Relationships Among Variables (analytictech)
• Help its giving me percentages for this and I dont know what to do 💀
• I'm confused because the video is going too fast.
• Change the playback speed so you will understand better.
• I don't really understand this. This is pretty hard.
• I don't get it.
• Can someone please help me with this math please? I don't get the explanation from this video. What is Sal trying to do? how can you do this in an easier way?
• Hi, I have a question in the exercises (2.1):
I think it should be w=5/4*v, because 4w=5v (400 ml of water for every 500 ml of vegetables), and we dived both sides with 4, and the result is w=5v/4, that is the same thing as w=5/4*v