Tales by Dots and Lines is Chapter 5 of Class 8 Maths Ganita Prakash Part 2. This chapter helps students understand data in a more meaningful way using number lines, dot plots, graphs, and different methods of analysing information.
Instead of only learning formulas, students explore concepts like mean as a balance point, median, effect of extreme values, and visual representation of data. These ideas help students understand how numbers can tell a story when they are arranged properly.
Practicing CBSE Board Class 8 Maths Chapter 5 Tales by Dots and Lines MCQs with Answers helps students revise important concepts and check their understanding of data handling. These MCQs focus on observation, calculation, and reasoning skills required for better exam preparation.
Students can also practice more Class 8 MCQs to strengthen different subjects. Regular practice of Class 8 Maths MCQs helps improve accuracy, speed, and confidence while solving mathematical problems.
Chapter 5 Tales by Dots and Lines Class 8 Maths MCQs with Answers
Practice these MCQs to revise important concepts of mean, median, dot plots, frequency, line graphs, and data interpretation from Class 8 Maths Chapter 5 Tales by Dots and Lines.
Q. A data set contains the numbers 8, 10, 12, 14, and 16. Which value represents the balance point of this data?
A. 10
B. 12
C. 14
D. 16
Answer: B. 12
Explanation: The mean represents the balance point of data. Mean = (8 + 10 + 12 + 14 + 16) ÷ 5 = 60 ÷ 5 = 12.
Q. Which measure represents the middle value after arranging data in order?
A. Mean
B. Highest value
C. Median
D. Frequency
Answer: C. Median
Explanation: Median represents the centre value of arranged data. It helps identify the middle position of a data set.
Q. If a number equal to the current mean is added to a data set, what will happen to the mean?
A. It remains the same
B. It becomes double
C. It always decreases
D. It becomes zero
Answer: A. It remains the same
Explanation: Adding a value equal to the existing mean does not change the balance point of the data.
Q. The scores of five players are 14, 16, 20, 24, and 26. Find the median score.
A. 16
B. 20
C. 24
D. 26
Answer: B. 20
Explanation: The data is already arranged. The middle value among five observations is 20, so it is the median.
Q. Which measure changes more when an extremely large or small value is added to data?
A. Median
B. Frequency
C. Mean
D. Number of values
Answer: C. Mean
Explanation: Mean uses all values in its calculation, so extreme values or outliers affect it more.
Q. In a dot plot, several dots placed above one value show:
A. The value appears repeatedly
B. The value should be ignored
C. The value is always the mean
D. The value is incorrect
Answer: A. The value appears repeatedly
Explanation: Multiple dots above a number represent its frequency or how many times that value occurs.
Q. If the average of 6 numbers is 12, what is their total sum?
A. 60
B. 72
C. 84
D. 90
Answer: B. 72
Explanation: Sum of observations = Mean × Number of observations = 12 × 6 = 72.
Q. The numbers 4, 5, 6, 7, and 40 are given. Which statement is correct?
A. The outlier affects the mean more
B. Median changes the most
C. All values become equal
D. The outlier has no effect
Answer: A. The outlier affects the mean more
Explanation: The value 40 is an outlier. Such extreme values have a greater effect on the mean than the median.
Q. Which representation is most suitable for showing rainfall changes over several months?
A. Frequency table only
B. Line graph
C. Random number list
D. Single observation
Answer: B. Line graph
Explanation: Line graphs are useful for showing changes, patterns, and trends over a period of time.
Q. The mean of two numbers 18 and 30 will be:
A. Less than both numbers
B. Greater than both numbers
C. Exactly between both numbers
D. Equal to 30 only
Answer: C. Exactly between both numbers
Explanation: The mean of two numbers lies halfway between them. Here, (18 + 30) ÷ 2 = 24.
Q. Why are dot plots useful while studying data?
A. They remove repeated values
B. They make patterns and frequency easier to see
C. They change the data values
D. They replace all calculations
Answer: B. They make patterns and frequency easier to see
Explanation: Dot plots visually represent data and help identify repeated values, clusters, and gaps.
Q. The marks obtained by students are 9, 12, 15, 18, and 21. What is the mean?
A. 12
B. 15
C. 18
D. 21
Answer: B. 15
Explanation: Mean = (9 + 12 + 15 + 18 + 21) ÷ 5 = 75 ÷ 5 = 15.
Q. For an even number of observations, how is the median calculated?
A. By taking the largest number
B. By adding all observations only
C. By finding the average of two middle values
D. By choosing the smallest number
Answer: C. By finding the average of two middle values
Explanation: When the number of observations is even, the median is the mean of the two middle values.
Q. What is the first step before finding the median of any data set?
A. Arrange the data in order
B. Multiply all numbers
C. Remove repeated numbers
D. Find the largest value only
Answer: A. Arrange the data in order
Explanation: Median depends on the position of values, so arranging data correctly is necessary.
Q. A school records the number of students present every day for a month. Which tool can show the daily changes clearly?
A. Line graph
B. Single value
C. Unarranged list
D. Random calculation
Answer: A. Line graph
Explanation: A line graph helps observe increases and decreases in values over time.
Q. A frequency table is mainly created to:
A. Change original values
B. Arrange and summarise large data
C. Remove important information
D. Avoid comparing numbers
Answer: B. Arrange and summarise large data
Explanation: Frequency tables organise information and show how often each value occurs.
Q. The average of 10, 14, 18, and 22 is:
A. 12
B. 14
C. 16
D. 18
Answer: C. 16
Explanation: Mean = (10 + 14 + 18 + 22) ÷ 4 = 64 ÷ 4 = 16.
Q. What does the mean represent when data values are shown on a number line?
A. The balance point of values
B. Only the largest number
C. Only the smallest number
D. A missing value
Answer: A. The balance point of values
Explanation: Mean works as the balancing point where values on both sides create an equal balance.
Q. If the mean of four numbers is 20, find their total.
A. 60
B. 70
C. 80
D. 100
Answer: C. 80
Explanation: Total = Mean × Number of values = 20 × 4 = 80.
Q. Which statement about an outlier is correct?
A. It can strongly affect the mean
B. It always removes the median
C. It makes data impossible to study
D. It cannot appear in graphs
Answer: A. It can strongly affect the mean
Explanation: An outlier is an extreme value that can shift the mean because mean considers all observations.
Q. If there is no dot above a number in a dot plot, what does it mean?
A. The value occurs many times
B. The value is not present in the data
C. The value is always the median
D. The value is the highest frequency
Answer: B. The value is not present in the data
Explanation: No dot above a number means that particular value does not occur in the data set.
Q. When a data set contains extreme values, which measure is usually more stable?
A. Median
B. Mean
C. Total sum
D. Highest value
Answer: A. Median
Explanation: Median depends on position, so it is less affected by very large or very small values.
Q. An upward movement in a line graph usually represents:
A. Decreasing values
B. Increasing values
C. Missing information
D. Equal values only
Answer: B. Increasing values
Explanation: A rising line graph shows that the values are increasing over time.
Q. The mean of 6, 8, x, and 14 is 10. Find the value of x.
A. 8
B. 10
C. 12
D. 14
Answer: C. 12
Explanation: Required total = 10 × 4 = 40. Therefore, x = 40 − (6 + 8 + 14) = 12.
Q. The number of times a value appears in data is called:
A. Frequency
B. Median
C. Balance point
D. Difference
Answer: A. Frequency
Explanation: Frequency shows how many times a particular observation occurs in a data set.
Q. Why are graphs and dot plots used in data handling?
A. To remove information
B. To make data harder
C. To understand information visually
D. To avoid comparisons
Answer: C. To understand information visually
Explanation: Visual representations help students observe patterns and understand data quickly.
Q. Find the median of 11, 15, 19, 23, and 27.
A. 15
B. 19
C. 23
D. 27
Answer: B. 19
Explanation: The middle value of the arranged data is 19, so the median is 19.
Q. If 4 is added to every value in a data set, what happens to the mean?
A. It increases by 4
B. It decreases by 4
C. It remains unchanged
D. It becomes zero
Answer: A. It increases by 4
Explanation: When the same value is added to every observation, the mean also increases by the same value.
Q. Tales by Dots and Lines mainly helps students improve:
A. Data analysis and reasoning skills
B. Only memorising formulas
C. Drawing without understanding
D. Guessing answers
Answer: A. Data analysis and reasoning skills
Explanation: This chapter develops the ability to understand, organise, and interpret data using different methods.
Q. Which tool is useful for observing changes in population over different years?
A. Single number
B. Line graph
C. Random list
D. Unarranged table
Answer: B. Line graph
Explanation: A line graph is suitable for representing changes and trends over a continuous period.
Chapter 5 Tales by Dots and Lines At a Glance
| Chapter | Details |
|---|---|
| Class | 8 |
| Subject | Maths |
| Book | Ganita Prakash Part 2 |
| Chapter Number | Chapter 5 |
| Chapter Name | Tales by Dots and Lines |
| Main Concepts | Mean, Median, Dot Plots, Line Graphs, Data Interpretation |
| Question Type | MCQs with Answers and Explanations |
Important Concepts From Chapter 5 Tales by Dots and Lines
Mean as a Balance Point
Mean is one of the most important concepts discussed in this chapter. Students learn that mean is not only a formula but also represents the balance point of a data set.
For two numbers, the mean lies exactly between them. For a larger group of numbers, the values below and above the mean balance each other on a number line. This approach helps students understand why mean represents the central value of given data.
Learning mean visually also makes it easier to analyse different real-life situations where averages are used, such as marks, scores, and measurements.
Understanding Median in Data
Median represents the middle value of a data set when all values are arranged in order. It helps students understand the centre of data from a different perspective.
Unlike mean, the median does not change much because of extremely high or low values. This makes it useful when students need to understand data where some values are very different from others.
A clear understanding of median helps students compare information and choose the correct method for analysing data.
Effect of Outliers on Mean and Median
An outlier is a value that is much higher or lower compared to the other numbers in a data set. This chapter helps students understand how such values can affect the final result.
Mean changes easily when an extreme value is added because every number contributes to the calculation. Median usually remains more stable because it depends on the position of values.
Understanding this difference helps students decide which measure represents the data better.
Dot Plots and Data Representation
Dot plots are simple visual tools that represent data using dots on a number line. Instead of reading a long list of numbers, students can quickly understand patterns through a dot plot.
Dot plots help identify repeated values, clusters, gaps, and overall distribution of data. They make information easier to observe and compare.
This concept improves students' ability to understand data visually and answer reasoning-based questions.
Line Graphs and Data Trends
Line graphs are used to represent changes in information over a period of time. They help students identify whether values are increasing, decreasing, or remaining stable.
Examples like temperature changes, population growth, and other measurements can be understood easily using line graphs.
Learning line graphs improves data interpretation skills and helps students connect Maths with real-life situations.
How to Score Better in Chapter 5 Tales by Dots and Lines MCQs
Scoring well in this chapter becomes easier when students focus on understanding data instead of memorising only formulas.
Follow these simple preparation tips:
- Understand the meaning of mean and median clearly.
- Practice finding the balance point of different data sets.
- Arrange values correctly before finding the median.
- Observe dot plots carefully before answering questions.
- Understand how outliers affect mean and median.
- Practice reading information from line graphs.
- Check calculations carefully to avoid small mistakes.
Strong observation and regular practice help students solve data-based MCQs with better accuracy.
