# Frequency tables assignment

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An instructor asks students to rate their anxiety level on a scale of 1 to 100 (1 being low anxiety and 100 being high anxiety) just before the students take their final exam. The responses are shown below. Construct the table for the instructor using six classes.

48,50,71,58,56,55,53,70,63,74,64,33,34,39,49,60,65,84,54,58

• 141 \$41\$
•
• 23 \$3\$
•
• 342 \$42\$
•
• 450 \$50\$
•
• 53 \$3\$
•
• 651 \$51\$
•
• 759 \$59\$
•
• 86 \$6\$
•
• 960 \$60\$
•
• 1068 \$68\$
•
• 114 \$4\$
•
• 1269 \$69\$
•
• 1377 \$77\$
•
• 143 \$3\$
•
• 1578 \$78\$
•
• 161 \$1\$
•

Note that the data is not ordered and that we have been asked to use 6 classes.

To determine the class width, use the formula:

Max Value−Min ValueNumber of Classes=84−336=8.5

Since the data values are integers, round up to the next integer, 9. The minimum value, 33, is the lower class limit of the first class. To find all other lower class limits, add the class width, 9. For example, the second lower class limit would be: 33+9=42.

Lower Class Limit Upper Class Limit Frequency
33
42
51
60
69
78

The upper class limit for each row is one less than the lower class limit from the following row. For example, the upper class limit for the first row is 42−1=41. You can also add the class width to one upper class limit to get the upper class limit for the next row.

Lower Class Limit Upper Class Limit Frequency
33 41
42 50
51 59
60 68
69 77
78 86

To find the frequency for each class, count the number of data values that fall within the range of each class. For example, the data values 33, 34, and 39 fall within the range of the first class, 33-41. So, the frequency of this class is 3.

Lower Class Limit Upper Class Limit Frequency
33 41 3
42 50 3
51 59 6
60 68 4
69 77 3
78 86 1