Assertion and Reason Questions on Statistics
Question 1
Assertion (A): The mean is affected by extreme values in a data
set.
Reason (R): The mean is calculated by dividing the sum of all
values by the number of values.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: The mean is sensitive to extreme values because it
uses all data points in its calculation.
Question 2
Assertion (A): The median is a better measure of central
tendency when data is skewed.
Reason (R): The median is calculated by arranging the data in
order and finding the middle value.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: The median is less affected by outliers, making it
more representative in skewed distributions.
Question 3
Assertion (A): The mode is the most frequently occurring value
in a data set.
Reason (R): The mode can be found by organizing the data in
ascending order.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: B) Both A and R are true, but R is not the correct
explanation of A.
- Explanation: While the mode is indeed the most frequent value,
it does not necessarily require the data to be organized in order.
Question 4
Assertion (A): A data set can have more than one mode.
Reason (R): A data set is bimodal if it has two modes and
multimodal if it has more than two.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: A data set can have multiple modes, which can be
classified as bimodal or multimodal.
Question 5
Assertion (A): The range is a measure of dispersion in a data
set.
Reason (R): The range is calculated as the difference between
the maximum and minimum values.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: The range measures how spread out the values are
by focusing on the extremes.
Question 6
Assertion (A): The interquartile range (IQR) is a robust
measure of dispersion.
Reason (R): The IQR is calculated using the first and third
quartiles, excluding outliers.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: The IQR focuses on the central 50% of the data,
making it less sensitive to outliers.
Question 7
Assertion (A): The mean can be calculated from grouped data.
Reason (R): Grouped data summarizes information in intervals,
which allows for the calculation of the mean.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: The mean can be calculated using midpoints of the
intervals in grouped data.
Question 8
Assertion (A): The sum of deviations of data values from the
mean is always zero.
Reason (R): The mean is the point at which the total distance
from all values is minimized.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: This property of the mean ensures that the sum of
positive and negative deviations equals zero.
Question 9
Assertion (A): The mode is the best measure of central tendency
for categorical data.
Reason (R): Categorical data does not have a meaningful average
or median.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: The mode effectively represents the most common
category in categorical data.
Question 10
Assertion (A): The median divides a data set into two equal
parts.
Reason (R): The median is the middle value when the data is
arranged in order.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: The median splits the data into two halves, with
equal numbers of data points on either side.
Question 11
Assertion (A): Quartiles are used to summarize the spread of a
data set.
Reason (R): Quartiles divide the data into four equal parts.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: Quartiles help to identify the distribution and
spread of data by segmenting it into parts.
Question 12
Assertion (A): The variance is a measure of how far each number
in a data set is from the mean.
Reason (R): Variance is calculated as the average of the
squared deviations from the mean.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: Variance quantifies the dispersion of data points
around the mean by squaring deviations.
Question 13
Assertion (A): Standard deviation is the square root of the
variance.
Reason (R): Standard deviation provides a measure of dispersion
in the same units as the data.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: The standard deviation relates directly to the
data's scale, making it more interpretable than variance.
Question 14
Assertion (A): A box plot visually represents the five-number
summary of a data set.
Reason (R): The five-number summary includes minimum, first
quartile, median, third quartile, and maximum.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: The box plot effectively displays the five-number
summary, highlighting the distribution of the data.
Question 15
Assertion (A): The data set with the smallest interquartile
range (IQR) is the most consistent.
Reason (R): A smaller IQR indicates that the central 50% of
data points are closer together.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: A smaller IQR reflects less variability in the
middle of the data set, indicating consistency.
Question 16
Assertion (A): When comparing two data sets, a higher mean
indicates a higher overall value.
Reason (R): The mean is influenced by all values in the data
set.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: The mean summarizes the data effectively and
reflects the overall level of values in the set.
Question 17
Assertion (A): The median is not affected by extreme outliers
in the data.
Reason (R): The median is determined solely by the middle
value(s) in the ordered list.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: Since the median depends only on the middle value,
it remains stable despite extreme values.
Question 18
Assertion (A): Cumulative frequency helps in understanding the
distribution of data.
Reason (R): Cumulative frequency shows the total number of data
points that fall below a certain value.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: Cumulative frequency provides insight into how
data accumulates, which aids in distribution analysis.
Question 19
Assertion (A): The probability of an event is always between 0
and 1, inclusive.
Reason (R): A probability of 0 means the event will not occur,
while 1 means it will definitely occur.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: This is a fundamental principle of probability,
reflecting certainty and uncertainty.
Question 20
Assertion (A): Outliers can significantly affect the mean and
standard deviation of a data set.
Reason (R): Outliers are extreme values that do not conform to
the rest of the data.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: Outliers can skew the mean and inflate the
standard deviation, impacting data interpretation.
Question 21
Assertion (A): A bar graph is used to represent categorical
data.
Reason (R): In a bar graph, the height of each bar represents
the frequency of each category.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: Bar graphs are effective in displaying categorical
data through visual frequency representation.
Question 22
Assertion (A): A histogram is similar to a bar graph but is
used for continuous data.
Reason (R): In a histogram, the bars are adjacent to each
other, indicating continuous intervals.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: Histograms illustrate the frequency distribution
of continuous data through connected bars.
Question 23
Assertion (A): Data can be represented using a pie chart.
Reason (R): A pie chart shows the proportional sizes of parts
to a whole.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: Pie charts effectively display parts of a whole,
emphasizing the distribution of categorical data.
Question 24
Assertion (A): In a frequency distribution, the class intervals
should be mutually exclusive.
Reason (R): This ensures that each data point belongs to one
and only one interval.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: Mutual exclusivity is crucial for accurate
representation and analysis of data.
Question 25
Assertion (A): Data representation is essential in statistics
for effective communication of information.
Reason (R): Graphs and charts can simplify complex data and
make it more accessible.
- A) Both A and R are true, and R is the correct explanation of A.
- B) Both A and R are true, but R is not the correct explanation of A.
- C) A is true, but R is false.
- D) A is false, but R is true.
- Answer: A) Both A and R are true, and R is the correct
explanation of A.
- Explanation: Visual aids enhance understanding and allow for
quicker insights into data trends.