A survey of 300 union members in New York State reveals that 112 favor the Republican candidate for governor. Construct a 90% confidence interval for the percentage of all New York State union members who favor the Republican candidate.

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.