Which of the following would be the easiest to use to determine the quartiles of a data set: histogram, dot plot, stem and leaf plot, or cumulative relative frequency plot?
The answer would be the cumulative relative frequency plot.
In order to find the quartiles with a cumulative relative frequency plot, all you have to do is draw horizontal lines at 25%, 50%, and 75%, then note the values that correspond to the intersections of the frequency plot and the horizontal lines.
- A frequency distribution gives the number of occurences of a data point in the set.
- A relative frequency distribution divides the frequency by the total number of data points, giving a percentage for each data value.
- A cumulative relative frequency distribution takes the percentage for each value and adds them, culminating with the last value at 100%. In effect, it tells the percent of data values below a given value.