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Current time:0:00Total duration:3:09

Reading pie graphs (circle graphs)

Video transcript

for the past year Travel Agency has collected data about the number of individual tickets that it sells for signature product a Mediterranean cruise the monthly data on ticket sales is shown below what are the best and worst months for cruise sales so what they've given us this diagram this is usually called a pie chart or pie graph because it looks like a pie that sliced up into a bunch of pieces sometimes this is called a circle graph but pie graph is much more common and then they say it's monthly ticket sales so each of these slices represent the sales in a given month so for example this blue slice over here represents the sales in January and the way that a pie chart is set up each slice is bigger or smaller depending on what fraction of the hole it represents so for example they're telling us in January they sold 18 percent of the total year's ticket sales in generous if you add up all of these percentages it should add up to a hundred percent and not only do they tell us that they sold eighteen percent but the slice of this pie should be eighteen percent of the area of the entire pie it is literally eighteen percent of the pie if you were to eat this slice you would have eaten 18 percent of the pie now that out of the way let's think let's think about their questions what are the best and the worst months for cruise sales so the best month is obviously the month where they sell where they have the largest or the largest percentage of their tickets were sold and actually I started with January and if you just and this is what's neat about pie graphs you wouldn't even have to look at the numbers January just jumps out as the biggest slice of pie if you didn't even see the numbers if you couldn't even read and you just looked at this and someone said what is the largest slice of pie you would immediately say hey this is clearly the largest slice of pie right over there and so that is actually the best month for cruise sales because they sold 18 percent you see this 18 percent is larger than all of the other percentages over here but it's clear just by looking at the graph this is the largest slice now what's the worst month for cruise ticket sales the worst month well then we just have to find the thinnest slice of pie and if we look over here that the slices of pie get pretty thin out down here this is in the summer in June and July and in May but the smallest are actually July and June and this is where the numbers become useful because when you when you just look at it by you know when you just eyeball it you're not sure hey are these exactly the same or they just look exactly the same and that's where these numbers are valuable and based on the data they've given us it looks like these are tied for the worst in terms of ticket sales in both of these months they sell only 3% in each month so the worst months for cruise sales are July and June July and June are tied for the worst the best is clearly January and then after January the next-best on it they're not really asking us add but since we have the pie chart in front of us might as well ask ourselves that what's the next best but looks like November is slightly better than December but in general in general it's pretty clear that the winter months the winter months do much better in terms of cruise sales and these over here and I guess people are looking to get away from from the cold