00:02
In this question, we have here the dot plot, which each dot represents an observation.
00:07
So in this case, for example, in zero, we have one observation.
00:13
For one we also has one, but for two, you have one, two, and so on.
00:21
So you need to count how many you have of each, so that you can find the mean, for example.
00:28
So in part a, we are interested in the mean.
00:29
The mean is you need to add the values, the number of pets, that each one of those 25 people that they own.
00:40
In this case, what we're going to do is we're going to do zero plus one.
00:46
But then two, we have three people saying that they have two, so we can multiply it by three.
00:52
Or three, we have to multiply by four.
00:55
Four, it is the one that we have the largest amount.
01:00
Five, we have five, six we have two, seven, we also have two, and then eight we only have one.
01:09
And when we add this, we get 102 pets for this total number of 25 people.
01:17
So now to find the mean, we just need to find the ratio here of the total number of pets out of the total number of people.
01:27
And that is 408.
01:31
Now for b, we find the median.
01:33
The median, we first find the position, which is given by the number of observations plus 1 over 2.
01:40
In this case, this will be 26 over 2, which is 13.
01:45
Because this is a whole number, that means that we have to find only what is the observation, from the smallest to the highest number of pets, that is in the position 13.
01:56
So if you count, you're going to see that the value that is in the position 13 is the number 4.
02:03
It's one of the possible numbers, possible number of people, like one of those six, that said they have four pets...