Grouped Distribution Frequency

The data presented in the table have a mean value of:

• 172

• 161

• 157

• 184

The table shows the distribution of the number of hours worked each week (on average) for a sample of 100 community college students. The mean

• 50

• 34.6

• 20

• 36.8

The class mark of the class 250 - 280 is ______

• 255

• 260

• 265

• 270

Answer explanation

Class mark = (Lower limit + Upper limit)/2 = (250 + 280)/2 = 265

In a frequency distribution, the mid - value of a class is 25 and the width of the class is 20. The lower limit of the class is _____

• 25

• 15

• 10

• 20

Answer explanation

Mid - value = 25 Width = 20 Lower limit = Mid value of class - (Width/2) = 25 - (20/2) = 25 - 10 = 15

Choose the correct frequency distribution table for the data on height (cm) of 20 girls using the class intervals 130 - 135, 135 - 140 and so on. The heights of the girls in cm are: 139, 138, 144, 147, 165, 142, 149, 155, 149, 141, 134, 136, 131, 146, 160, 153, 133, 148, 140, 138

• 
• 
• 
• 

Answer explanation

The frequency distribution of weights (in kg) of 50 persons is given. What are the class marks of all the class interval?

• 30, 40, 50, 60, 70

• 35, 45, 55, 65, 75

• 30.5, 40.5, 50.5, 60.5, 70.5

• 35.5, 45.5, 55.5, 65.5, 75.5

Answer explanation

Class mark = (Lower limit + Upper limit)/2 1) (30 + 40)/2 = 35 2) (40 + 50)/2 = 45 3) (50 + 60)/2 = 55 4) (60 + 70)/2 = 65 5) (70 + 80)/2 = 75

The table above is what type of Frequency Distribution?

• Ungrouped Frequency Distribution

• Grouped Frequency Distribution

• Histogram

• Tally Table

What is the class width of the given grouped frequency distribution?

• 84

• 5

• 17

• 30

Is the given histogram the correct representation of the grouped frequency table above?

• Yes, because the heights of the bars are accurately aligned with the given frequencies.

• Yes, because the bars have no gaps.

• No, because the first bar must start at 11, yet it started at 0.

• No, because the intervals used the term "to" instead of the symbol dash (-).

A listing, often expressed in a chart form, that pairs values of a variable with their frequency.

• Frequency

• Frequency Distribution Table

• Histogram

• Tally