80 78 75 81 76 89 74 Test scores 82 85 Send data to calculator Test scores 71 5 to 75 5 75 5 to 79 5 79 5 to 83 5 a Complete the grouped frequency distribution for the data Note that the class width is 4 83 5 to 87 5 74 87 5 to 91 5 83 90 Frequency 73 88 0 0 0 82 79 b Using the classes from part a draw the frequency polygon for the data Note that you can add or remove classes from the figure Label each class with its midpoint Frequency 6 5 4 3 2 Test scores L