Please help me! Gabriella sold half of her comic books and then bought fifteen more. She now has 34. How many comic books
did she have in the beginning?

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.