HW #10 problem #3a
Suppose that 49 students were selected from a large lecture anthropology class.
(a) What proportion of students in this sample got at least a 75?
This is how I am doing 3a:
%Z=(75- 76.8571428571429)/( 10.6144555520604/sqrt(49))%
Z = -1.22 -> tables the prob = 0.1112
(1-0.1112)=0.8888
Please help.
Comments
I think you may be over-complicating this. When it asks for "What proportion of students" it is looking for one value over another, in this case, number of students. So be sure to use your table to compare the number it asks for (i.e. number of students who got at least 75) over the total number of students in the sample.
Hope this helps!