# QNT 275 Final Exam 2017 – Cumulative Frequency Distribution of Commuting Time

The following table gives the cumulative frequency distribution of the commuting time (in minutes) from home to work for a sample of 400 persons selected from a city.

Time (minutes) f

• 0 to less than 10 64
• 0 to less than 20 153
• 0 to less than 30 217
• 0 to less than 40 283
• 0 to less than 50 352
• 0 to less than 60 400

The sample size is:

400

The percentage of persons who commute for less than 30 minutes, rounded to two decimal places, is:

Take the cumulative total values less than 30 minutes 217, then divide by 400. Multiply by 100 for the percentage.

54.25%

The cumulative relative frequency of the fourth class, rounded to four decimal places, is:

The cumulative relative frequency is the same as the previous question, but stays a decimal. For the forth group it is 283/400.

0.7075

The percentage of persons who commute for 40 or more minutes, rounded to two decimal places, is:

Subtract 283 from 400, then divide by 400.

29.25%

The percentage of persons who commute for less than 50 minutes, rounded to two decimal places, is:

Divide 352 by  400.

88.00%

The number of persons who commute for 20 or more minutes is:

(400-217) /400

45.75%

• Student: Lonny McDowell
• Textbook: QNT 275 Statistics Fundamentals
• Course: QNT 275 Final Exam 2017