9th STB _ STATISTICS

What is the formula to calculate the mean of a set of numbers?

• Mean = (Sum of all numbers) + (Total count of numbers)

• Mean = (Sum of all numbers) / (Total count of numbers)

• Mean = (Sum of all numbers) * (Total count of numbers)

• Mean = (Sum of all numbers) - (Total count of numbers)

Calculate the mean of the following numbers: 10, 15, 20, 25, 30

• 18

• 28

• 20

• 22

Define median and explain how to find it in a set of numbers.

• The median is the sum of all numbers in a set

• The median is the middle value in a set of numbers when they are arranged in ascending or descending order. If the set has an odd number of values, the median is the middle number. If the set has an even number of values, the median is the average of the two middle numbers.

• The median is only applicable to sets with prime numbers

• The median is always the highest value in a set

Find the median of the following set of numbers: 5, 10, 15, 20, 25

• 10

• 20

• 30

• 15

What is the mode of a dataset?

• The mode is the average of the dataset

• The mode is the highest value in the dataset

• The mode is the lowest value in the dataset

• The mode of a dataset is the value that appears most frequently.

Identify the mode in the following dataset: 2, 4, 6, 6, 8, 10, 10

• 2

• 8

• 4

• 6, 10

Differentiate between primary and secondary data.

• Primary data is obtained from secondary sources.

• Secondary data is collected firsthand by the researcher.

• Primary data is less reliable than secondary data.

• Primary data is collected firsthand by the researcher, while secondary data is obtained from existing sources.

When is secondary data more suitable than primary data?

• When the information is outdated

• When the data is expensive to obtain

• When the data needs to be specific to the research question

• When the required information is already available

What type of graph is this?

• Bar Graph
• Line Plot
• Pictograph
• Tally Chart

For calculating median, all items of the series are arranged in:

• Ascending order

• Descending order

• Ascending or descending order