Which frequency table shows the test times in minutes for a reading test 81,63, 61,58, 72, 70, 79,68, 82,64, 54,82, 72,63, 64,76, 57,65, 73,58
Test Time (Min) Frequency
54 - 60 4
61 - 63 4
64 - 70 4
71 - 76 4
77 - 82 4
To create a frequency table for the given test times, follow these steps:
Step 1: Arrange the data in ascending order:
54, 57, 58, 58, 61, 63, 63, 64, 64, 65, 68, 70, 72, 72, 73, 76, 79, 81, 82, 82
Step 2: Determine the range, which is the difference between the highest and lowest test time values:
Range = Highest value - Lowest value = 82 - 54 = 28
Step 3: Decide on the number of intervals or classes. This value can be chosen based on the data range and the desired level of detail. In this case, let's choose 5 intervals.
Step 4: Calculate the width of each interval by dividing the range by the number of intervals:
Interval width = Range / Number of intervals = 28 / 5 ≈ 5.6 (rounding to a convenient value, usually 5 or 10)
Step 5: Determine the lower limit for the first interval. This can be the lowest test time or any other value less than the lowest test time. In this case, let's choose 50 as the lower limit.
Step 6: Create intervals by adding the width to the lower limit successively. Calculate the upper limit for each interval. Round the upper limit to the nearest convenient value like 5 or 10:
- Interval 1: 50 - 55 (54, 57)
- Interval 2: 55 - 60 (58, 58, 61)
- Interval 3: 60 - 65 (63, 63, 64, 64, 65)
- Interval 4: 65 - 70 (68, 70, 72, 72, 73, 76)
- Interval 5: 70 - 75 (79, 81, 82, 82)
Step 7: Count the frequency (number of occurrences) for each interval:
- Interval 1: 2
- Interval 2: 3
- Interval 3: 5
- Interval 4: 6
- Interval 5: 4
Step 8: Create the frequency table, showing the intervals and their respective frequencies:
Interval Frequency
_____________________
50 - 55 2
55 - 60 3
60 - 65 5
65 - 70 6
70 - 75 4
This is the frequency table for the given test times.