00:01
So this question is regarding the class interval of the test resolvers versus the frequency distribution.
00:08
The question asks you to find out mean, median, and mode.
00:10
Mean is the average.
00:15
Mean can be calculated by, first of all, the midpoint times the number, i guess, the f or the frequency.
00:27
Let's write it down.
00:30
Midpoint of the interval times the f which is the frequency of each interval and this is the sum and then you're gonna have to divide by the total number so in this case you have interval all the way from 15 to 24 then 25 to 34 4 and all the way to 94.
01:11
So for each interval, you're going to have to calculate the midpoint.
01:15
So the midpoint for each interval can be calculated by the lower number plus the high number divided by 2.
01:34
So for example, the first interval which is 15 lower plus 24 higher divided by 2.
01:43
So this equals 19 .5.
01:47
Then, this is the first interval.
01:50
Second is 25 and 34.
01:56
25 plus 34 divided by 2.
02:02
The second midpoint is 29 .5.
02:08
And the third is 35 plus 44 divided by 2.
02:19
This equals 39 .5.
02:23
The next midpoint is interval 45 to 54.
02:31
So this one is 49 .5.
02:44
The next interval is 55 plus 64, 59 .5.
02:55
Keep going.
02:57
65 plus 74, 69 .5.
03:04
And then the next one is 75 plus 84, 79 .5.
03:15
And lastly, 85 plus 94, 89 .5.
03:26
So now we add these midpoints together times the frequency.
03:41
So the first one is 19 .5.
03:51
19 .5.
03:53
Now we know the frequency is 5...