Statistics Fourth Class Quiz

Study Notes

Midpoint Calculation

For the fourth class interval 0.51-0.58, the midpoint is calculated as (0.51 + 0.58) / 2, resulting in 0.545.
For the fourth class interval 0.54-0.62, the midpoint is (0.54 + 0.62) / 2, which equals 0.58.

Cumulative Frequency

Cumulative frequency for the fourth class (7.3-7.9) is 39, summing the frequencies: 10 (fourth class) + 12 (third class) + 13 (second class) + 4 (first class).
Cumulative frequency for the second class (5.9-6.5) totals 17, by adding the frequencies of the second class (13) and first class (4).

Class Width Definition

Class width can be defined as the difference between the lower limits of consecutive classes; for example, using the first class (30-47) and second class (48-65), the calculation yields 17 (48 - 30).

Frequency Table Analysis

The score of 110.6 falls into the class interval 102-119.
For scores between 30 and 101, the total frequency is 38, found by adding frequencies of the fourth class (11), third class (14), second class (10), and first class (3).

Frequency Distribution for Satisfaction Percentages

Frequency distribution for customer satisfaction percentages:
- 75.0-76.9: 2
- 77.0-78.9: 1
- 79.0-80.9: 3
- 81.0-82.9: 6
- 83.0-84.9: 6

Class Width in Price Data

Analyzing prices of plasma televisions, the class width is determined as 50, calculated from the lower limits of the first class (1014) and second class (1064) (1064 - 1014 = 50).

Frequency and Relative Frequencies in Price Data

Frequency of the first class (1014-1063) is 2, counting the relevant values (1029, 1027).
The relative frequency of the third class (1114-1163) equals 0.285, computed by dividing the frequency of the class (6) by total frequencies (21): 6/21.
Cumulative frequency of the third class is 11, summing its frequency (6) with frequencies of classes below it.

Homework Hours Distribution

For the second class (16-21), the relative frequency is 0.111, calculated as 3 (frequency of second class) divided by total frequencies (27): 3/27.
The relative frequency for the third class (22-27) is 0.333, calculated by dividing the class frequency (9) by total frequencies (27): 9/27.

Description

Test your understanding of determining midpoints and cumulative frequency for classes in statistics. This quiz covers examples from the fourth class, helping solidify your knowledge on frequency distribution. Perfect for students looking to master statistical concepts.