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Main content
Current time:0:00Total duration:2:28
AP.STATS:
UNC‑1 (EU)
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UNC‑1.I (LO)
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UNC‑1.I.3 (EK)

Video transcript

Miguel tracked how much sleep he got for 50 consecutive days and made a histogram of the results which interval contains the median sleep amount and so they're saying is that this interval on the histogram from 6 to 6.5 or this one or this one or any of these which of these intervals contain the median pause this video and see if you can figure that out alright now let's work through this together and let's just remind ourselves how we find the median if I had the data points 11 9 7 3 & 2 the way that we find the median is we can order it from least to greatest or actually you could do it from greatest to least but let's do least to greatest so 2 3 7 9 11 and the median would be the middle number and have a clear middle number because I have five data points if I have an even number of data points I still would want to order them from least to greatest so let's say that I have a 1 1 3 and a 7 but here you don't have a clear middle so the median would be the mean of the middle two numbers so in this situation Miguel has an even number of data points so the median would be the mean of the 25th and 26th data point these would be the middle two data points so which interval here contains the 25th and the 26th the data point well we can start at the bottom so we have actually let's just look at each interval and think about how many data points they have in it this one has two this one has nine this one has 12 and I'm just reading out how many data points there are in each of these intervals this one has 12 this one has 11 I see that there this one has two and this one has two so if we look at just this we have the two lowest if we look at the two bottom intervals combined we have the 11 lowest if we look at the three bottom intervals we have the 11 plus 12 you have the 23 lowest so this is the 23 lowest data points and so the 24th 25th 26th the next 12 data starting from the bottom starting from the lowest are going to be in this next interval here and we care about the 25th and the 26th so they're definitely going to be in this interval from 7.5 hours of sleep to 8 hours of sleep
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