Two different means of assessing the students have been suggested. First using a normal distribution and secondly using fixed percentages for each rating.

Using the normal distribution

A - > 2a

B - > a and < 2a

C - > -a and < a

D - > -2a and < -a

E - < -2a

Using the fixed percentage

A - > 80%

B - > 60% and < 80%

C - > 40% and < 60%

D - > 20% and < 40%

E - < 20%

The task is tothe two different assessment procedures. You should consider the outcome if a teacher sets ancompare and contrasteasier testor aharder test.

You many assume that the standard deviation remains the same for each of the tests.

I have no idea where to start. Any help would be greatly appreciated.

NOTE: I have used "a" because i could not find sigma.