Distribution question, please HELP!?

Question

Is the following an example of normal distribution?

Justin received an average mark of 82%.

The mean for his class was 71.325
The median was 72.5
The standard deviation was 9.2636248
Including Justin, there are 40 people in his class

30 students were within one standard deviation of the mean
38 students were within two standard deviations of the mean
All 40 students were within three standard deviations of the mean


Marks:

48
53
54
55
59
63
63
63
64
64
66
67
69
70
70
71
71
72
72
72
73
74
75
75
75
75
76
76
76
77
77
78
78
78
79
81
82
85
87
90

Answer 1

I don't think it is.. To have normal distribution you have to have a set with the mode answer being the median answer. ie more people would have to have 72 than any other result. Which is not true in this case. (More people have 75). The key to find out if it is normal distribution is when you draw the graph of test results against frequency. The graph should look like a speed bump. With the most frequency in the middle and the least on the outsides. (Also the median result is 72 and not 72.5. The median is the middle result). A link below is an example of Normal distribution.

Answer 2

In a perfectly normal distribution, the mean and the median are the same (here it's quite close), 67% of data are within 1 std dev of the mean (here it's 75%), 95% are within 2σ (here it's 95%), 99% are within 3σ (here it's 100%). I'd say that's close enough for government work.

Answer 3

This is not an example of
normal distribution ,because
in normal distr. the mean is the
same with the median.
Also i cannot underrstand
what are you asking.
Please rewright your question
again and I will try to answer y6ou.

Answer 4

Yea the problem is normally distributed..
the sample size is greater than 30..

Answer 5

yes