H girls play hockey. N girls play netball and B girls play both. a) How many girls play hockey but not netball?
b) How many girls play netball or hockey?

The major difference is that a histogram is only used to plot the frequency of score occurrences in a continuous data set that has been divided into classes, called bins.  bar charts, on the other hand, can be used for a great deal of other types ofvariables  including  ordinal  andnominal  data sets.