WEBVTT
00:00:00.820 --> 00:00:06.340
Find, to two decimal places, the mean of the test scores in the table.
00:00:07.040 --> 00:00:11.380
Then determine which groupâ€™s score is closest to the mean.
00:00:12.550 --> 00:00:15.940
We have eight class groups from A to H.
00:00:16.290 --> 00:00:20.380
The test scores range from 70 to 93.
00:00:21.540 --> 00:00:25.370
The first part of this question wants us to calculate the mean.
00:00:25.900 --> 00:00:30.750
We do this by dividing the sum of the values by the number of values.
00:00:31.690 --> 00:00:42.830
We need to add 78, 86, 72, 93, 92, 84, 87, and 70.
00:00:43.530 --> 00:00:47.250
This gives us a total of 662.
00:00:48.300 --> 00:00:54.490
As there are eight class groups altogether, we need to divide 662 by eight.
00:00:55.350 --> 00:00:58.680
This gives us 82.75.
00:00:59.600 --> 00:01:05.030
The mean test score is therefore equal to 82.75.
00:01:05.920 --> 00:01:12.450
The second part of the question asks us to work out which group is closest to this mean value.
00:01:13.580 --> 00:01:19.140
The test score that is immediately above 82.75 is 84.
00:01:20.070 --> 00:01:24.550
And the test score that is immediately below the mean is 78.
00:01:25.310 --> 00:01:32.080
As 82.75 is closer to 84 than 78, this is the correct answer.
00:01:33.090 --> 00:01:38.250
Group F score of 84 is the one that is closest to the mean.