L2 MEASURES OF CENTRAL TENDENCY OF UNGROUPED DATA

What is a measure of central tendency?

• Standard Deviation

• Variance

• Mean

• Range

Answer explanation

A measure of central tendency is a statistical measure used to determine the center of a data set. The mean is a common measure of central tendency, representing the average value of the data.

Which of the following is a summary measure that describes a whole set of data with a single quantity representing the middle or center of its distribution?

• Mode

• Median

• Variance

• Mean

Answer explanation

The mean is a summary measure that represents the center of a data set by calculating the average of all values, making it the correct choice in this scenario.

What is the most commonly used measure of central tendency for ungrouped data?

• Mean

• Median

• Mode

• Standard Deviation

Answer explanation

The most commonly used measure of central tendency for ungrouped data is the Mean.

What formula is used to calculate the mean of a set of data?

• Sum of x plus n

• Sum of x divided by n

• Sum of x minus n

• Sum of x multiplied by n

Answer explanation

The correct formula to calculate the mean of a set of data is the sum of x divided by n.

In a biology class of 20 students, 6 friends received test grades of 92, 84, 65, 76, 88, and 90. What is the mean of their test scores?

• 85.5

• 82.5

• 88.5

• 78.5

Answer explanation

The mean of the test scores is calculated by adding all scores and dividing by the number of students. (92+84+65+76+88+90)/6 = 82.5

What is the median of the ages of the five contestants in a statistics quiz, which are 18, 17, 18, 19, and 18?

• 17

• 18

• 18.5

• 19

Answer explanation

The median is the middle value when the data is ordered. In this case, the ages are 17, 18, 18, 18, 19. The middle value is 18, so the median age is 18.

In a blood pressure check, the blood pressures of seven mothers were recorded as 135, 121, 119, 116, 130, 121, and 131. What is the median blood pressure?

• 131

• 130

• 119

• 121

Answer explanation

The median blood pressure is the middle value when the data is arranged in ascending order. The blood pressures are: 116, 119, 121, 121, 130, 131, 135. Since there are 7 values, the median is the 4th value, which is 121.

What is the mode of the data set: 15, 28, 25, 48, 22, 43, 39, 44, 43, 49, 34, 22, 33, 27, 25, 22, and 30?

• 22

• 25

• 30

• 27

Answer explanation

The mode is the number that appears most frequently in the data set. In this case, 22 appears three times, which is more frequent than any other number in the set, making it the mode.

The speed of 10 stenographers in typing per minute are: 110, 120, 119, 112, 121, 118, 115, 107, and 115. What is the mode of the data set?

• 121

• 118

• 115

• 110

Answer explanation

The mode is the number that appears most frequently in the data set. In this case, 115 appears twice, which is more frequent than any other number.

What is the weighted mean formula used to calculate the grade point average?

• Sum of w divided by n

• Sum of x times w divided by sum of w

• Sum of x multiplied by w

• Sum of x divided by n

Answer explanation

The weighted mean formula for calculating the grade point average is the sum of x times w divided by the sum of w.