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### Course: AP®︎/College Statistics > Unit 1

Lesson 2: Representing a categorical variable with graphs# Reading bar graphs: movies

Sal interprets bar graphs to answer questions about a context.

## Want to join the conversation?

- will bar graphs always be vertical like this or could the bars also be horizontal?(21 votes)
- They both can if you still wondered(13 votes)

- Sal did it take you a long time to get all these right? It of course took me a long time.(17 votes)
- It depends,some people can solve it faster than others(1 vote)

- can someone explain what marginal distributions is?(4 votes)
- Isn't the X and Y supposed to be labeled there since it's "Reading bar graphs"?(4 votes)
- I cannot view this video in restricted mode. I am sure this is an error. Is there someone who can get YouTube to change this for this video? We've never had this problem in Khan before.(4 votes)
- It is probably just an error because wi fi can be messed up sometimes.(1 vote)

- Hi well I have a question for you do you take your videos out of khan?(4 votes)
- yeah that,s what i thougth(0 votes)

- Because Sal needed an example from real life.(4 votes)

- why is it so hard and so high??(3 votes)
- cool fact 1+1 is 2 :)(3 votes)

## Video transcript

- [Voiceover] Lola asked her classmates their favorite type of movie
and graphed the results. All right so it says that 20 people said their favorite type
of movie was comedy. Six people said their favorite
type of movie was scary. 10 people said their favorite
type of movie was adventure. 10 people also said their favorite type of movie is cartoons. And then 16 people said their favorite type of movie is a mystery. All right, so let's
read the questions here. So which of the following types of movies were picked by fewer than 14 people? So fewer than 14 people. So more than 14 picked comedy or mystery. So this line right over here would be 14. So fewer than 14 were
scary, adventure, cartoon. This was six people, 10
people, and 10 people. Scary, adventure, and cartoon. So we wanna pick scary,
adventure, and cartoon. These three had less
than 14 people pick them. So let's do a couple more of these. Let's do a couple more. Puppy Party Place graphed
the number of dogs that came in each weekday. So let's see, 80 dogs came in on Monday, 160 dogs came in on Tuesday,
80 dogs came in on Wednesday. 140 dogs came in on Thursday, and then Friday was a very popular day, 180 dogs came in to the
Puppy Party Place on Friday. All right, so what are they asking us? On which day did the same number of dogs come to Puppy Party Place, as on Monday and Wednesday combined? All right, so let's see,
Monday and Wednesday combined. So on Monday we had 80 puppies
come there, or 80 dogs. And on Wednesday we had 80 dogs. And they're saying which day had the same as Monday and Wednesday combined? So Monday and Wednesday
combined would be 80 plus 80, which would be 160. So on which of these
days did 160 dogs come? Well we see it right over here, 160 dogs, that was on Tuesday, and only on Tuesday. So Tuesday, let's do a few more of these. Dessert Zone asked its customers about their favorite ice cream flavor, and graphed the results. So 175 customers said
vanilla, 225 said chocolate, 75 said strawberry, and
200 said cookie dough. All right, how many more customers picked the most popular flavor than
the least popular flavor? All right, so the most
popular flavor was chocolate, that was 225, and the
least popular flavor... To the least popular flavor,
it's a tongue twister, was 75. So how many more picked the most popular than the least popular? Well the most popular was
225, the least popular was 75. So what's 225 minus 75? Let's see, 225 minus 25 would be 200, minus 50 would be 175. Minus 75 would be 150. So we get 150 customers. And once again, we're saying that 150 more customers picked chocolate, the most popular flavor,
than the least popular. Another way you could do it is you could look at the least popular
and the most popular and say well how many
more do I have to add to the least popular to
get to the most popular? And you see 25, 50, 75, 100, 125, 150. Each of these lines is 25 more. So there you have it, 150 more customers liked the most popular flavor, chocolate, than the least popular flavor.