Answer: To find the range of the marks obtained, we need to find the difference between the highest and lowest marks:
Range = highest mark - lowest mark
To find the highest and lowest marks, we can simply sort the marks in ascending or descending order:
39, 48, 56, 75, 76, 81, 85, 85, 90, 95
So, the highest mark is 95 and the lowest mark is 39. Then, the range is:
Range = 95 - 39 = 56
To find the mean marks obtained by the group, we need to add up all the marks and divide by the number of marks:
Mean = (85 + 76 + 90 + 85 + 39 + 48 + 56 + 95 + 81 + 75) / 10
= 745 / 10
= 74.5
So, the mean marks obtained by the group is 74.5.
Explanation: