yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

Modeling with multiple variables: Roller coaster | Modeling | Algebra II | Khan Academy


2m read
·Nov 10, 2024

We're told a roller coaster has c cars, each containing 20 seats, and it completes r rides a day. Assuming that no one can ride it more than once a day, the maximum number of people that can ride the roller coaster in a single day is p. Write an equation that relates p, c, and r. Pause this video and see if you can do that.

All right, before I even look at the variables, I'm just going to try to think it out in plain language. So what we want to think about is what is the max number of people per day? People per day, and so that's going to be equal to the number of cars in our roller coaster, so number of cars times the maximum number of people per car. Times the max number per car, so this would just tell you the maximum number of people per ride.

So then we have to multiply it times the number of rides per day. So times, we do this in a new color, times number of rides per day. Now what are each of these things? They would have either given us numbers or variables for each of them. The max number of people per day, that's what we're trying to set on one side of the equation. That is this variable p right over here.

So we'll say capital P is equal to what's the number of cars per coaster? I guess you could say, let me write it this way, per coaster, per roller coaster. So they give us that right over here. A roller coaster has c cars, so that's going to be this variable here in orange, or this part of it, that's c.

Now, what's the maximum number of people per car? Well, they say each containing 20 seats, so I'd multiply that times 20 for this part. And then I want to multiply that times the number of rides per day for the entire roller coaster, so that's going to be times r. And we're done.

We could rearrange this a little bit; we could write this as p is equal to 20 times c times r, and we're done.

More Articles

View All
Solving square-root equations: no solution | Mathematics III | High School Math | Khan Academy
Let’s say that we have the radical equation: the square root of 3x minus seven plus the square root of 2x minus one is equal to zero. I encourage you to pause the video and see if you can solve for X before we work through it together. Alright, so one t…
High Speed photography 101 - Pre-Smarter Every Day
Hey, it’s me, Destin. It is late; the kids are in bed, so it’s time to work on the next project. This time around, we’re going to start trying to take photos of stuff being hit by bullets. I think that moment that they’re hit by bullets is called high-spe…
15 Mistakes You Make In Your 30s
Your 30s are a time of transition and change. You had 10 years of trial and error, and now it’s time to get serious. These are 15 mistakes you can’t afford to make anymore. Welcome to Alux. Number one: Not thinking of retirement. Newsflash! If you only r…
Giving Up On The Stock Market
What’s up, guys? It’s Graham here. So, for the past century, the stock market has been a tried and true method for building your wealth, making passive income, and growing your money to the point of never needing to work another day in your entire life e…
Taking a Family Road Trip | National Geographic
(Calm music) [Corey] I feel most alive when I’m out exploring. (Acoustic music) We’re taking our son on a road trip to Wallowa-Whitman National Forest in Eastern Oregon. There’s something special about looking out on the open road. You never really kno…
Determining whether values are in domain of function
We’re asked to determine for each x value whether it is in the domain of f or not, and they have our definition of f of x up here. So pause this video and see if you can work through this before we do it together. All right, so just as a bit of a review,…