Answer:
Explanation:
a. The height of each bar is marked with the number of students it represents. So, the total number of students is the total of the numbers indicating bar height:
3 + 14 + 21 +12 + 6 = 56
56 students took the exam.
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b. The class interval or class width is the difference between the scores at the edges of the class. Here, the first class has an interval of 60 -50 = 10. All the other classes have the same interval.
The class interval is 10.
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c. The midpoint of a class is the average of the endpoints. For the first class, it is ...
(50 +60)/2 = 55
The midpoint for the first class is 55.
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d. There are two bars below 70. The numbers at the top of those bars are 3 and 14, so the total number of students that scored below 70 is ...
3 + 14 = 17
17 students earned a score less than 70.