The passage looks to be a part of literary piece and it is written in past tense

4.1 Interpretation 1: Raw marks of learners (Progress Achievement Test): Oral Test Component

Group	No of learners	Raw marks
X	5	8, 8, 9, 8, 9
Y	9	4, 3, 4, 5, 6, 3, 3, 4, 4
Z	12	1, 1, 1, 2, 1, 1, 2, 1, 2, 1, 3, 1

There were 26 learners in all three groups. The same test was administered to the three groups. Marks are given out of 10 for this oral component.

At first sight, we are able to draw simple conclusion that each group is homogeneous in that there exists considerable degree of ‘between group variance’. However, central tendency measures provide more reliable information about the average and typical performances of students in the oral component.

The mean values (the sum of all scores of all students in one group divided by the number of students) indicate that average performance of learners varies considerably from one group to the other. Mean values of the three groups are 8.4, 4.00 and 1.39 respectively. However, there is danger in considering merely the mean values to understand the average performances of the learners: it is possible that two groups may have the same mean value, (though not in this case) but the spread of scores may be different: while in one group, all the learners may obtain similar scores, in the other group, there may be a wider spread of scores. Thus the variability measures such as standard deviation (SD)⁴, mode and median need to be taken into consideration, the results of which are summarized below:

Central tendency measure	Group X	Group Y	Group Z
Mean value	8.40	4.0	1.39
Mode	8	4	1
Median	8	4	1
SD	0.57	1.07	0.69

Measures of central tendency ( post test): stylistic competence

Standard Deviation, which is the squire root of the average squire distance of the scores from the mean value, is considerably low in each case, which indicates that within group variability of performance is relatively less. Even in group Y, which has comparatively a greater distribution, the SD lies below 1.1: in this group, the scores are more widely distributed among the different students. However, both the mode, which is the score obtained by the largest number of subjects, and the median, which is the score which divides the group into two in such a way that half of the scores are above it and half are below it, are 4, which is equal to the mean value.

Mean values: oral component ( group X,Y, Z )
Thus each group itself is not heterogeneous but we can find greater degree of ‘between group variability’.