WEBVTT
00:00:01.320 --> 00:00:06.480
Evaluate the arithmetic mean between negative 77 and 24.
00:00:08.000 --> 00:00:14.360
In order to calculate the arithmetic mean of a set of numbers, we divide the sum of the values by the number of values.
00:00:15.080 --> 00:00:22.520
In this question, we need to add negative 77 and 24 and then divide the answer by two.
00:00:23.440 --> 00:00:28.640
Negative 77 plus 24 is equal to negative 53.
00:00:29.320 --> 00:00:34.880
This means that the arithmetic mean is equal to negative 53 over two.
00:00:36.000 --> 00:00:42.000
We could also write this as the decimal negative 26.5.
00:00:43.440 --> 00:00:55.240
An alternative method to calculate the arithmetic mean would be to consider a number line, in this case, between negative 77 and 24.
00:00:56.400 --> 00:01:02.320
The mean would be the midpoints between these two values.
00:01:03.360 --> 00:01:10.360
We know that to get from negative 77 to zero, we need to add 77.
00:01:11.120 --> 00:01:16.080
We need to add another 24 to get to 24.
00:01:16.880 --> 00:01:22.880
This means that the difference between negative 77 and 24 is 101.
00:01:23.880 --> 00:01:30.840
We need to add 101 to get from negative 77 to 24.
00:01:32.360 --> 00:01:37.200
A half of 101 is 50.5.
00:01:38.040 --> 00:01:54.560
This means that the midpoint of negative 77 and 24 will be 50.5 greater than negative 77 and 50.5 less than 24.
00:01:55.400 --> 00:02:04.760
This is equal to negative 26.5 or negative 53 over two as previously calculated.