How to prove that class A scores are higher than classs B

[tnaser]

Hi

If I have grades of 2 classes and ranked , how can I prove that class A scores higher than class B with statically significant difference?

Example:
Rank - Grade - class
1- 100 - A
2- 99 - A
3- 97 - B
4- 95 - B
5- 90 - A
..

Thanks

 

[stapel]

What is the exact text of the exercise? Also, what are your thoughts so far?

Please be complete. Thank you!

 

[tnaser]

What is the exact text of the exercise? Also, what are your thoughts so far?

Please be complete. Thank you!

It is not exercise , so no complete text. I was thinking to do a weighted rank or ranking correlation

 

[DrPhil]

It is not exercise , so no complete text. I was thinking to do a weighted rank or ranking correlation

Could you elaborate more on using ranking instead of actual scores? I don't find a good exposition of the method in my handbook.

What came to my mind was to find mean and std.dev. for each class, and then to look at possible tests.