Are these practice questions for Tales by Dots and Lines based on the CBSE pattern?

Yes. Every practice question is modeled on the CBSE Class 8 Mathematics exam pattern — including MCQs, assertion-reason questions, and short-answer formats that frequently appear in CBSE papers.

Are the practice questions for Tales by Dots and Lines free?

Yes. Every chapter includes free practice questions for Class 8 students to get you started.

What types of questions are included?

The practice set for Tales by Dots and Lines mainly includes MCQs and CBSE-style short-answer questions, with instant feedback on each answer. For full-length textbook practice, use the NCERT Solutions page.

Are the practice questions suitable for board exam preparation?

Yes. The questions test the same concepts and depth that CBSE asks in board exams. After finishing, also solve the NCERT and NCERT Exemplar exercises for Tales by Dots and Lines for full coverage.

How many practice questions are there for Tales by Dots and Lines?

The number scales with chapter length and concept density. Each chapter typically has 15-50 practice questions across MCQ and short-answer formats.

Tales by Dots and Lines Class 8 Mathematics Practice Questions with Answers

easy

Name the type of graph that is generally used to visualize how data changes over time.

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easy

A dataset is {2, 4, 6, 14}. A student proposes that the mean is 8. Justify whether this is correct or incorrect without calculating the sum, by only evaluating the distances of the data points from the proposed mean.

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easy

The median of an ordered dataset is 18. If each value in the dataset is multiplied by 3, analyze the effect and find the new median.

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easy

Solve for the value of

p

if the mean of the numbers 8, 12, 15,

p

, and 11 is 12.

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easy

Define the 'median' of a data set.

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easy

Calculate the mean of the first six even natural numbers.

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easy

List the steps to find the median of the following data set: 15, 8, 22, 11, 6.

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easy

Calculate the median of the following dataset: 25, 15, 30, 10, 20.

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easy

A line graph shows a city's average monthly temperature. The line segment connecting the points for July and August is a horizontal line. Justify what this signifies about the temperature in those two months.

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easy

Summarize the information presented in a frequency table. What do the 'Number' and 'Frequency' columns tell us?

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easy

From a line graph showing the monthly rainfall in a city for a year, identify what the horizontal and vertical axes typically represent.

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easy

Define the 'mean' of a data set.

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easy

The mean of a dataset is 40. If 10 is subtracted from each value in the dataset, what is the new mean? Analyze the effect.

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medium

Explain what happens to the mean of the data set {4, 6, 8} if a new value, 2, is included.

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medium

A data set has 10 values and its mean is 20. Explain what the sum of these 10 values is.

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medium

The average age of a group of 12 friends is 14 years. When a new friend joins, the average age becomes 14.2 years. Calculate the age of the new friend. Then, if another friend whose age is 16 years leaves this new group, what is the final average age?

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medium

Recall the effect on the mean if every value in a data set is doubled.

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medium

The mean weight of 9 players on a team is 60 kg. One player, who weighs 68 kg, leaves the team. Two new players join, and the mean weight of the new 10-player team becomes 61 kg.

Formulate and execute a plan to find the mean weight of the two new players.
If one of the new players weighs 70 kg, create and solve an equation to find the weight of the second new player.

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medium

The line graph shows active users for App A and App B. Evaluate the claim: "App A is growing faster than App B from January to April." Justify your conclusion by referring to the change in user numbers.

Graph Data:

App A: Jan(10k), Feb(15k), Mar(18k), Apr(20k)
App B: Jan(5k), Feb(10k), Mar(15k), Apr(20k)

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medium

Propose two distinct numbers that can be added to the dataset {5, 10, 15} without changing its mean, and justify your proposal.

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medium

Summarize the steps to find (a) the total marks for each student and (b) the average marks for each subject using a spreadsheet, given a table with student names in rows and subject names in columns.

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medium

Describe how the mean acts as a 'balancing point' for a data set. Use the example data: 2, 5, 11.

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medium

Design a dataset of 7 data points representing the number of goals scored by a football team in 7 matches, such that the mean is 4, the median is 3, and the mode is 2. Justify that your created dataset meets all three conditions.

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medium

A dataset is 10, 15, 20, 25, 30. Analyze the effect on the mean if a new value, 40, is included in the dataset. Calculate the new mean.

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medium

Create a set of 5 distinct integers where the mean is greater than the median.

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medium

The mean of two numbers is 15. If one of the numbers is 12, solve for the other number.

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medium

A survey recorded the number of hours students spend on digital devices on a school day versus a weekend day. School Day Data (hours): {1, 2, 2, 2, 3, 3, 4, 5} Weekend Day Data (hours): {3, 4, 4, 5, 5, 6, 7, 8}

Propose the most effective type of graph to visually compare these two datasets. Justify your choice.
Formulate three distinct conclusions by interpreting the data.

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medium

Explain what happens to the median of the data set {10, 20, 30, 40, 50} if a new value, 60, is included.

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medium

The table shows the size of families in a small housing society. Calculate the mean family size.

Family Size	Frequency
3	5
4	8
5	2

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medium

Compare the mean of the first 5 multiples of 3 with the mean of the first 5 multiples of 4.

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medium

Describe the process of calculating the mean for a set of data presented in a frequency table. Use the following table as an example to explain the steps:

Value (x)	Frequency (f)
5	2
10	3

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medium

In a spreadsheet, what does the formula =SUM(B2:B8) represent?

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medium

The weights (in kg) of 7 students are 45, 52, 48, 50, 43, 49, 46. Calculate the mean and median weight.

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medium

A student's scores in 5 consecutive math tests were 75, 82, 78, 90, and 85. A line graph is plotted for these scores. Analyze the data to calculate the student's average score and the range of the scores.

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medium

Formulate a general rule for the new mean of a dataset if every value in the set is multiplied by a constant k and then a constant c is added to each. Justify your formula using an algebraic proof.

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medium

Create a dataset with 5 distinct numbers whose median is 20. Then, propose a value that could be added to your dataset so that the median of the new set of 6 numbers is still 20. Justify your choice.

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hard

The monthly pocket money of 6 friends is: ₹200, ₹250, ₹150, ₹300, ₹220, ₹280. Calculate the mean pocket money. If each friend's pocket money is increased by 10% for the next month, analyze this change to calculate the new mean pocket money without listing all the new values. Justify your method.

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hard

A company's marketing team created a line graph to show a 'dramatic' profit increase from Year 1 to Year 4. Data: Year 1: ₹50 Lakh, Year 2: ₹51 Lakh, Year 3: ₹53 Lakh, Year 4: ₹54 Lakh. The graph's Y-axis (Profit) starts at ₹48 Lakh and ends at ₹55 Lakh.

Critique the graph. Explain one specific way it is designed to be misleading.
Propose how you would redesign the graph to represent the data fairly, describing the key change.
Calculate the percentage increase in profit from Year 1 to Year 4 and justify if the word 'dramatic' is appropriate.

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hard

Formulate and prove a theorem regarding the mean of a set of n consecutive integers. Start by testing cases for n=3 and n=5, then create a general proof for any n starting with any integer a.

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hard

The monthly salaries of 5 employees are: ₹20,000, ₹22,000, ₹25,000, ₹28,000, and ₹1,50,000. The owner claims, "The average salary in my company is ₹49,000, so our employees are very well-paid." Critique this statement. Propose a more appropriate measure of central tendency to represent a 'typical' salary and justify your choice with calculations.

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hard

A dot plot shows the number of goals scored by a football team in its last 10 matches. The 9 known data points are 2, 0, 3, 1, 2, 4, 1, 2, 3. The mean number of goals for all 10 matches was 2.1. Apply the concept of mean to find the missing data value. Then, determine the median of the complete 10-match dataset.

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hard

The median of the data 11, 14,

x

, 23, 27, 30, which is already arranged in ascending order, is 19. Solve for the value of

x

.

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hard

The dot plot shows dots at the following numbers: 11, 12, 12, 14, 18, 19, 20. A student claims the mean is 15. Without calculating the actual mean, evaluate this claim by analyzing the sum of distances on either side of 15. Is the true mean greater than, less than, or equal to 15? Justify your reasoning.

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hard

Evaluate the statement: "Adding two new values to a dataset with an odd number of entries, one smaller than the original median and one larger than the original median, will never change the median."

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hard

Explain the difference in how the mean and median are affected by an outlier (an extremely high or low value). Use the data set {10, 12, 14, 16, 100} to illustrate your explanation.

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Tales by Dots and LinesClass 8 Mathematics Practice Questions