HW#3 - I’m confused by what a 2% bin size means. I don’t know how many bins to set for the histogram

JFF Answer:

The grade scale is from 0% to 100%. So a 2% bin size means breaking the grade scale into 50 bins if the MINIMUM grade is a zero and a MAXIMUM grade is a 100.

In order to override the default for the 'histogram' function in matlab, you can specify the "bin edges" and then the number of bins.  The bin width is (upper limit edge - lower limit edge)/nbins. See Matlab HELP on 'histogram' for details as to setting the BinEdges, NumBins, and BinWidth.