Class 9 Practice Level 3 – Set 1 – Statistics

Total questions: 15

The mean of 12 numbers is 24. If two numbers 30 and 18 are removed, what is the new mean of the remaining numbers?

Topic: Mean

None

Find the median of the data set: 42, 46, 50, 38, 54, 48, 60, 44, 52, 40.

Topic: Median

None

The data set 23, 25, 25, 27, 28, 28, 28, 31, 30, 32 has two modes. What are they?

Topic: Mode

23 and 28

25 and 28

28 and 30

25 and 30

None

The mean of 8 numbers is 45. If each number is increased by 10%, what will be the new mean?

Topic: Mean

49.5

None

The range of the data set 150, 165, 170, 175, 185 is reduced by 20% when a number is added. What is the new range if the original range was 35?

Topic: Range

None

Determine the median for the following grouped data:

Topic: Median

Class intervals: 10-20, 20-30, 30-40, 40-50, 50-60 Frequencies: 5, 8, 12, 15, 10

37.5

42.5

None

The data set 20, 25, 30, 25, 35, 40, 25, 45, 50 has been altered by adding a new mode. If the original mode was 25, what could be the new mode?

Topic: Mode

None

If the range of a data set is 45 and a value 10 is added to each data point in the data set, what will be the new range?

Topic: Range

None

The mean of a certain number of observations is 35. If two additional observations, 30 and 40, are included, the new mean becomes 34.5. How many observations were there initially?

Topic: Mean

None

10.

The median of a frequency distribution is found to be 25. If all values in the data set are increased by 5, what will be the new median?

Topic: Median

None

11.

In a data set, the mode is 50, and all data points are multiplied by 3. What will be the new mode?

Topic: Mode

100

150

200

None

12.

The range of a data set was initially 120. If the maximum value is reduced by 10 and the minimum value is increased by 5, what will be the new range?

Topic: Range

105

115

125

130

None

13.

If the mean of 20 numbers is 50, and the mean of another set of 30 numbers is 40, what is the combined mean of all 50 numbers?

Topic: Mean

None

14.

A set of 9 observations has a median of 18. If one more observation is added and it is 20, what will be the new median?

Topic: Median

None

15.

In a set of data, 28 appears the most frequently. If 28 is added one more time to the set, will the mode change?

Topic: Mode

Yes

It depends on the number of data points

Cannot be determined

None

1 out of 15

Class 9 Practice Level 3 – Set 1 – Statistics

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