A Story of Numbers Class 8 (Ganita Prakash)
Master A Story of Numbers Class 8 (Ganita Prakash) with comprehensive NCERT Solutions, Practice Questions, MCQs, Sample Papers, Case Based Questions, and Video lessons.
NCERT Solutions
A Story of Numbers Class 8 (Ganita Prakash) – NCERT Solutions
Each question below opens its complete step-by-step Teachoo solution.
Figure it out - Page 60, 61
4 questionsQuestion 1
A group of indigenous people in a Pacific island use different sequences of number names to count different objects. Why do you think they do this?In very early human history, numbers were not thought of as "abstract" concepts (like the number 5 floating in the air). Instead, numbers were always attached to specific things (like "5 fish" or "5 coconuts").
View solutionQuestion 2
(i) Consider the extension of the Gumulgal number system beyond 6 in the same way of counting by 2s. Come up with ways of performing the different arithmetic operations (+, –, ×, ÷) for numbers occurring in this system, without using Hindu numerals. Use this to evaluate the following: Let’s remember are Gumulgal number system
Gumulgal (Australia)
urapon
ukasar
ukasar-urapon
ukasar-ukasar
ukasar-ukasar-urapon
ukasar-ukasar-ukasarWe note that it uses two words
urapon = 1
ukasar = 2
And the rest of the words are formed using these two
Question 3
Identify the features of the Hindu number system that make it efficient when compared to the Roman number system.The Hindu number system (which is the one we use today: 0, 1, 2, 3...) is much more efficient than Roman numerals (I, V, X, L...) for three main reasons:
View solutionQuestion 4
Using the ideas discussed in this section, try refining the number system you might have made earlier.We made an Orb System earlier
View solutionFigure it out - Page 69
3 questionsQuestion 1
Can there be a number whose representation in Egyptian numerals has one of the symbols occurring 10 or more times? Why not?The Egyptian system is
View solutionQuestion 2
Create your own number system of base 4, and represent numbers from 1 to 16.To create a Base-4 system, our "Landmark Numbers" must be powers of 4.
4^0=𝟏
4^1=𝟒
4^2=4×4=𝟏𝟔
Question 3
Give a simple rule to multiply a given number by 5 in the base-5 system that we created.Rule: The rule is to "Shift Up" every symbol to the next landmark.
View solutionFigure it out - Page 80
4 questionsQuestion 1
Why do you think the Chinese alternated between the Zong and Heng symbols? If only the Zong symbols were to be used, how would 41 be represented? Could this numeral be interpreted in any other way if there is no significant space between two successive positions?Let’s look at Zong and Heng Symbols again
The Chinese alternated between vertical and horizontal rod numerals to distinguish between place values clearly. This system helped avoid confusion, especially when numbers were written close together without a clear placeholder like zero (which was introduced later).
Question 2
Form a base-2 place value system using ‘ukasar’ and ‘urapon’ as the digits. Compare this system with that of the Gumulgal’s.This question asks to create a binary (Base-2) system using the words from the Gumulgal counting system introduced earlier in the chapter.
View solutionQuestion 3
Where in your daily lives, and in which professions, do the Hindu numerals, and 0, play an important role? How might our lives have been different if our number system and 0 hadn’t been invented or conceived of?Hindu numerals (0-9) and the concept of zero are the foundation of modern civilization.
Daily Life:
Commerce: Prices, banking, salaries, and splitting bills all rely on the decimal system.
Time: Digital clocks, calendars, and schedules.
Communication: Phone numbers, addresses, and IP addresses.
Professions:
Computer Science: Computers use binary (0 and 1), which is mathematically rooted in the concept of zero and place value. Without 0, we wouldn't have modern computing.
Engineering & Architecture: Precise measurements and calculations for buildings, bridges, and machines require efficient arithmetic that Roman numerals couldn't provide.
Science: Measuring distances to stars, calculating microscopic weights, or plotting graphs relies entirely on this efficient system.
Question 4
The ancient Indians likely used base 10 for the Hindu number system because humans have 10 fingers, and so we can use our fingers to count. But what if we had only 8 fingers? How would we be writing numbers then? What would the Hindu numerals look like if we were using base 8 instead? Base 5? Try writing the base-10 Hindu numeral 25 as base-8 and base-5 Hindu numerals, respectively. Can you write it in base-2?Why Base-10?
We likely use Base-10 because we have 10 fingers.
If we had 8 fingers:
We would likely use a Base- 𝟖 (Octal) number system.
Digits: 0, 1, 2, 3, 4, 5, 6, 7
Counting: After 7 , the next number would be " 10 " (which would represent the value 8)
Writing the number 25 (decimal) in other bases:
Decimal Number (Our System):
25
Drag to change the number
Base 10 (Decimal - 10 Fingers)
Why Learn This With Teachoo?
A Story of Numbers is Chapter 3 of NCERT Class 8 Ganita Prakash Part 1. It traces how different civilisations represented and calculated with numbers, from early counting mechanisms to Roman, Egyptian, Mesopotamian, Mayan, Chinese and Hindu systems. The chapter explains why place value, base and zero transformed mathematics. Teachoo organises the historical systems concept-wise and provides solutions for all listed Figure it out questions.
Why did number systems develop?
Counting begins with matching objects, marks or tokens to quantities. As trade, measurement, administration and astronomy grew more complex, societies needed symbols and procedures that could represent larger numbers and support calculation. The Mechanism of Counting examines the idea behind a representation, not just its symbols.
Roman numerals use combinations of fixed-value symbols and rules of addition or subtraction. They remain visible on clocks, monuments and headings but are inconvenient for long calculations because they lack a full positional place-value structure.
The Egyptian system used symbols for powers of ten and repeated them as needed. Students study variations, the notion of a base, addition and multiplication with Egyptian numerals and the role of the distributive law. The system’s strengths and shortcomings become clearer when it is compared with an abacus that uses decimal place value.
Place value, bases and the Hindu number system
The Mesopotamian system is associated with base 60, whose influence survives in time and angle measurement. The Mayan system used a different base structure, while the Chinese system developed efficient representations and counting tools. Comparing systems shows that the same quantity can be encoded in many ways.
The Hindu number system combines ten digits, positional decimal place value and zero as both a number and a placeholder. A symbol’s value depends on its position, making compact notation and standard algorithms possible. Its spread and evolution profoundly shaped global mathematics.
Topics covered on Teachoo
Teachoo includes:
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introduction and mechanisms of counting;
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early number systems;
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Roman numerals;
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Egyptian number representation;
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base and variations of the Egyptian system;
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Egyptian addition and multiplication;
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distributive law in Egyptian calculations;
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decimal abacus;
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shortcomings of non-positional representation;
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Mesopotamian, Mayan and Chinese systems;
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the Hindu number system;
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evolution of number representation; and
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Figure it out solutions for pages 60–61, 69 and 80.
Learning outcomes
Students should be able to read and interpret examples from different number systems, compare positional and non-positional notation and explain the meaning of a base. They should carry out simple calculations in a historical system, identify its limitations and describe why zero and place value make the Hindu decimal system efficient. They should also connect a representation with the needs of the society that used it.
Why is this chapter important?
The chapter presents mathematics as a human achievement shaped over centuries, not as a finished list of rules. Comparing systems reveals which features modern notation depends on. It deepens place-value understanding and prepares students for bases, computing, exponents and mathematical history.
How Teachoo supports learning
Teachoo separates each civilisation and mathematical idea, helping students revise without mixing symbol rules. Create a comparison table with columns for symbols, base, place value, zero and ease of calculation. Convert the same small number into several systems and compare the length and clarity of each representation.
When solving historical-numeral questions, state the value of each symbol and the rule used. For Egyptian multiplication, connect the steps to decomposition and the distributive property. Then use Teachoo’s worked solutions to check both the result and the interpretation.
Common mistakes to avoid
Do not apply Roman numeral rules to Egyptian, Mayan or other systems. A base does not mean the number of symbols always visible; it describes how place values or groupings progress. Avoid judging an older system only by modern convenience—identify what it could do well and where calculation became difficult.
Quick revision checklist
Choose one quantity and write it in Roman, Egyptian and modern Hindu-Arabic notation. For every form, state the rule used and whether position affects value. Then compare two historical systems by base, zero, place value and ease of calculation. Finish by explaining, in your own words, why a placeholder is necessary and why positional notation reduces the number of symbols needed for large values.
Deeper reasoning and concept connections
In A Story of Numbers (Ganita Prakash), fluency means more than repeating a procedure. Students should be able to recognise the underlying structure when the numbers, diagram, wording or orientation changes. A useful routine is: identify the mathematical objects, list the known and unknown quantities, state the governing property, carry out the steps and verify that every condition has been used.
Look for connections within the chapter as well. A definition usually leads to a representation; the representation reveals a pattern; and the pattern supports a rule or calculation. Explaining this chain improves retention and helps with case-based questions. It also prevents the common mistake of selecting a formula simply because its symbols resemble the numbers in the question.
How to solve unfamiliar and competency-based questions
Use a five-step response: interpret, represent, select, solve and verify. Interpret the wording; represent the information; select a definition, property or formula; solve without skipping the logical step; and verify through substitution, estimation, measurement or an alternative representation. This routine works for direct exercises as well as case-based questions.
If information appears unnecessary, ask whether it establishes a hidden condition. If information is missing, state what cannot be determined instead of inventing a value. In written answers, name the rule being used. Clear reasoning helps a teacher award method marks and also makes the page easier for a student—or an AI answer system—to retrieve for the precise doubt being asked.
What complete mastery looks like
For A Story of Numbers (Ganita Prakash), a student should be able to define the central ideas in simple language, recognise them in different representations, solve routine questions accurately and explain the method used. They should also be able to correct a flawed solution, create an example satisfying given conditions and combine two ideas from the chapter in one problem. A reliable mastery test is to solve one direct question, one application question and one reasoning question without looking at notes, then explain all three aloud or in writing.
Keep a compact error log with four labels: concept, interpretation, calculation and presentation. Reattempt each error after a gap instead of rereading the answer immediately. Improvement comes from correcting the decision that caused the mistake, not from repeating questions whose method is already known.
Additional frequently asked questions
What should a student know before starting A Story of Numbers (Ganita Prakash)?
Revise the definitions, number operations, diagrams or notation used at the beginning of the chapter. The prerequisite list should be short: if an earlier skill blocks progress, repair that skill with two or three focused questions and return to the chapter.
How can a student check an answer in A Story of Numbers (Ganita Prakash)?
Use an independent check whenever possible: substitute the result, reverse the operation, estimate its size, compare it with the figure, test a simpler case or solve using another representation. A check should examine the mathematical condition, not merely repeat the same arithmetic.
How many questions are enough for strong preparation?
There is no fixed number. Stop counting questions and track coverage: every concept, every standard method, at least one mixed problem, one competency-based problem and every previously incorrect type should be solved independently. Ten varied, analysed questions are more valuable than fifty copied solutions.
How should Teachoo solutions be used without becoming dependent on them?
Attempt the question first and mark the exact step where progress stops. Read only enough of the solution to repair that step, close it and restart the question. Finally, solve a similar problem without help. This turns a solution into feedback rather than a substitute for thinking.
Frequently asked questions
What is a positional number system?
It is a system in which a symbol’s value depends on its position, as in the decimal place-value system.
Why is zero important?
Zero represents the absence of a quantity and acts as a placeholder, distinguishing numbers such as 25, 205 and 2,005.
Which number systems are studied in this chapter?
The chapter examines early counting, Roman, Egyptian, Mesopotamian, Mayan, Chinese and Hindu number systems.
Treat every system as a mathematical design. Understanding its rules and limitations reveals why modern notation is so powerful.