Class 8 Mathematics Important Questions with Answers
Class 8 Mathematics is the last middle-school year before Class 9 polynomials and Euclid. Rational numbers get a full number-line treatment, linear equations move beyond one-step, and mensuration adds cubes and cylinders. This bank follows the rationalized NCERT so you are not revising deleted chapters. Search terms such as “class 8 rational numbers important questions” and “linear equations class 8 MCQ” open the matching chip. Twenty questions a page, answers folded.
Class 8 Mathematics is the last middle-school year before Class 9 polynomials and Euclid. Rational numbers get a full number-line treatment, linear equations move beyond one-step, and mensuration adds cubes and cylinders. This bank follows the rationalized NCERT so you are not revising deleted chapters. Search terms such as “class 8 rational numbers important questions” and “linear equations class 8 MCQ” open the matching chip. Twenty questions a page, answers folded. You are on the full Class 8 Mathematics bank (All Q&A), page 1 of 9 — 169 questions in this filter. This page lists mixed MCQ, short and long items so a weekly test feels like the school paper. Reveal a key only after you have written your own line. High-search phrases such as class 8 mathematics important questions and कक्षा 8 गणित प्रश्न उत्तर are mapped to these chips, not to an empty database shell. Phone layout: chapter chips scroll sideways, answers stay inside a tap, and the next page is a numbered link so Google and students both get a short URL. Updated for 2026 classroom practice on the rationalized NCERT.
Class 8 treats rationals as a system: closure, commutativity, associativity, distributivity, additive and multiplicative identities and inverses. The number line must accept −7/5 as a point, not a stain. Density — infinitely many rationals between two rationals — is the idea Class 9 will reuse. Standard form still wants a positive denominator. These questions mix properties with a little arithmetic so the property names are not empty labels.
2. Linear Equations in One Variable एक चर वाले रैखिक समीकरण
ax + b = c is only the start. Class 8 hides x in a fraction, in brackets, and in a word problem about consecutive integers or a two-digit number. Transposition plus a check by substitution is the method. Equations that reduce to a linear form after clearing denominators are still this chapter, not Class 10 pair of equations.
3. Understanding Quadrilaterals चतुर्भुजों को समझना
Sum of interior angles of an n-gon is (n−2)×180°. A parallelogram’s opposite sides and angles are equal; diagonals bisect each other. Rectangle, rhombus, square and kite are special cases with extra gifts. Class 8 asks you to name the smallest class that fits a figure, not to shout “square” at every four-sided shape.
Grouped frequency, class interval, histogram versus bar graph, and a pie chart whose 360° is the whole. Probability is still favourable over possible, now with a few “not equally likely” warnings. Read the class mark before you invent a mean formula from Class 10.
A square number ends with 0, 1, 4, 5, 6 or 9 — never 2, 3, 7, 8 in the unit place. Prime-factor method and long-division method both appear. Estimate √50 before you claim a calculator. Properties (√(ab)=√a√b for non-negatives) stop illegal steps such as √(a+b)=√a+√b.
Hardy’s taxi 1729 is optional folklore; unit-digit patterns and prime-factor cube roots are the marks. A perfect cube has exponents that are multiples of 3 in prime factorisation. Cube of a negative is negative. Keep that sign when the paper asks ∛(−125).
Compound interest enters: A = P(1+R/100)ⁿ. Discount, GST and successive percentage change are the shop-math cluster. A 10% rise and a 10% fall do not cancel. Convert ratio to percentage before you compare two offers. Time period and rate must share the same unit.
8. Algebraic Expressions and Identities बीजीय व्यंजक और सर्वसमिकाएँ
(a+b)², (a−b)², (a+b)(a−b) and (x+a)(x+b) are the four identities Class 8 actually uses. Expansion and factorisation are two directions of the same street. Degree and like terms still govern addition. Numericals such as 102² via (100+2)² are the speed items.
Lateral and total surface of cube, cuboid and cylinder; volume of the same three. A hollow cylinder is outer minus inner. Units: cm² versus cm³. π is 22/7 unless the question says 3.14. Do not bring Class 10 cone and sphere formulas unless a leftover school worksheet still prints them — this hub stays rationalized.
Negative exponents: a⁻ⁿ = 1/aⁿ. Scientific notation for very small and very large numbers. Laws remain the Class 7 set plus negatives. (10⁻³) is 0.001, not −1000. These MCQs punish sign errors more than memory of the law names.
11. Direct and Inverse Proportions प्रत्यक्ष और व्युत्क्रम अनुपात
x/y constant versus xy constant. More workers, fewer days is inverse if the work is fixed. A table that is not proportional is a trap question. Write the constant first, then the missing value.
Common factor, regrouping, identities, and the middle-term split for x²+5x+6. Factorisation is the reverse of expansion — check by multiplying back. Class 8 does not need the quadratic formula. Keep the common monomial outside before you split the quadratic.
A linear graph is a straight line in the Cartesian plane. Independent variable on x is a convention, not a law of nature, but exam graphs follow it. Reading a travel graph (time on x, distance on y) returns in Class 8 Science too. Plot integer points first; then join.
15+4=19। अंकगणित की जाँच इसी अध्याय के word problem से पहले करो।
Q.2MCQRational Numbers
कक्षा 8 Rational Numbers: 15 × 4 = ?
A. 45
B. 60
C. 19
D. 64
View the correct answer
Correct option: B — 60
गुणन 15×4=60।
Q.3MCQRational Numbers
Rational Numbers में यदि आधार संख्या 15 हो और एक चरण 4 जुड़े तो अगला पद?
A. 11
B. 19
C. 60
D. 0
View the correct answer
Correct option: B — 19
सरल वृद्धि: 15+4=19 — AP/समीकरण दोनों में यही जाँच काम आती है।
Q.4MCQRational Numbers
Rational Numbers: भिन्न 4/15 का दशमलव सन्निकटन किसके निकट?
A. 0
B. 0.27
C. 15
D. 4
View the correct answer
Correct option: B — 0.27
4÷15 ≈ 0.27।
Q.5MCQRational Numbers
Rational Numbers शब्द-समस्या में पहला कदम?
A. अंतिम उत्तर गढ़ना
B. ज्ञात-अज्ञात और मात्रक लिखना
C. केवल चित्र रंगना
D. फॉर्मूला बिना पढ़े रटना
View the correct answer
Correct option: B — ज्ञात-अज्ञात और मात्रक लिखना
NCERT numericals मात्रक और अज्ञात साफ चाहती हैं।
Q.6MCQRational Numbers
Rational Numbers में गलत सर्वसमिका/सूत्र चुनें।
A. जाँच के लिए छोटी संख्या रखें
B. दोनों पक्ष बराबर होने चाहिए
C. किसी भी दो पद जोड़कर नया सूत्र बना लें
D. मात्रक दोनों पक्षों पर समान
View the correct answer
Correct option: C — किसी भी दो पद जोड़कर नया सूत्र बना लें
मनगढ़ंत सूत्र Class 8 पेपर काटते हैं।
Q.7MCQRational Numbers
Rational Numbers अनुप्रयोग: 58 का 12% = ?
A. 46
B. 7
C. 70
D. 12
View the correct answer
Correct option: B — 7
58×12/100 = 7। प्रतिशत Comparing Quantities से पूरे गणित में चलता है।
Q.8ShortRational Numbers
Rational Numbers का एक सूत्र या नियम कक्षा 8 की भाषा में लिखें।
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Rational Numbers के NCERT नियम को परिभाषा + एक संख्यात्मक जाँच के साथ लिखें। उदाहरण: 15 और 4 रखकर दोनों पक्ष मिलाएँ।
Q.9ShortRational Numbers
Rational Numbers की एक आम गलती और सुधार।
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गलती: मात्रक या चिह्न छोड़ना / सूत्र अगली कक्षा का घुसाना। सुधार: प्रश्न की संख्याएँ लिखो, सूत्र NCERT वाला, उत्तर मात्रक सहित।
Q.10LongRational Numbers
Rational Numbers पर एक 4-अंक का हल लिखें जिसमें जाँच भी हो।
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दिया: संख्याएँ 15, 4।
विधि: अध्याय Rational Numbers का नियम लागू करें।
गणना: योग 19, गुणन 60।
जाँच: उलटा संक्रिया या प्रतिस्थापन।
अंत: शब्द-समस्या में वाक्य में उत्तर लिखें।
Q.11MCQRational Numbers
Class 8 Mathematics — Rational Numbers का NCERT फोकस सबसे सटीक कौन-सा है?
A. केवल रटंत तिथि-सूची बिना अवधारणा
B. Class 8 treats rationals as a system: closure, commutativity, associativity, distributivity,…
C. केवल Class 6 दोहराव
D. केवल deleted chapter का पुराना PDF
View the correct answer
Correct option: B — Class 8 treats rationals as a system: closure, commutativity, associativity, distributivity,…
यह अध्याय rationalized NCERT Class 8 में है। पैराग्राफ वही परीक्षा-फोकस दोहराता है।
Q.12ShortRational Numbers
Rational Numbers (कक्षा 8) को 3 पंक्तियों में लिखें — परिभाषा, एक उदाहरण, एक परीक्षा-चूक।
View the correct answer
परिभाषा: Rational Numbers / परिमेय संख्याएँ Class 8 Mathematics का पाठ है।
उदाहरण: NCERT चित्र या संख्यात्मक इसी अध्याय से लें।
चूक: अगली कक्षा का सूत्र या deleted पाठ न घुसाएँ।
Q.13LongRational Numbers
Class 8 Mathematics — Rational Numbers पर एक unit-test उत्तर लिखें (परिचय, 4 बिंदु, निष्कर्ष)।
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Class 8 treats rationals as a system: closure, commutativity, associativity, distributivity, additive and multiplicative identities and inverses. The number line must accept −7/5 as a point, not a stain. Density — infinitely many rationals between two rationals — is the idea Class 9 will reuse. Standard form still wants a positive denominator. These questions mix properties with a little arithmetic so the property names are not empty labels.
चार बिंदु: (1) NCERT परिभाषा/सूत्र/घटना। (2) एक उदाहरण या आरेख-विचार। (3) एक तुलना या कारण। (4) एक साधारण संख्यात्मक या उद्धरण यदि पाठ माँगता है।
निष्कर्ष: उत्तर अध्याय-सत्य रखें — बोर्ड की डेटशीट यहाँ नहीं गढ़ी गई।
Q.14MCQLinear Equations in One Variable
कक्षा 8 Linear Equations in One Variable: 16 + 5 = ?
A. 19
B. 21
C. 24
D. 80
View the correct answer
Correct option: B — 21
16+5=21। अंकगणित की जाँच इसी अध्याय के word problem से पहले करो।
Q.15MCQLinear Equations in One Variable
कक्षा 8 Linear Equations in One Variable: 16 × 5 = ?
A. 64
B. 80
C. 21
D. 85
View the correct answer
Correct option: B — 80
गुणन 16×5=80।
Q.16MCQLinear Equations in One Variable
Linear Equations in One Variable में यदि आधार संख्या 16 हो और एक चरण 5 जुड़े तो अगला पद?
A. 11
B. 21
C. 80
D. 0
View the correct answer
Correct option: B — 21
सरल वृद्धि: 16+5=21 — AP/समीकरण दोनों में यही जाँच काम आती है।
Q.17MCQLinear Equations in One Variable
Linear Equations in One Variable: भिन्न 5/16 का दशमलव सन्निकटन किसके निकट?
A. 0
B. 0.31
C. 16
D. 5
View the correct answer
Correct option: B — 0.31
5÷16 ≈ 0.31।
Q.18MCQLinear Equations in One Variable
Linear Equations in One Variable शब्द-समस्या में पहला कदम?
A. अंतिम उत्तर गढ़ना
B. ज्ञात-अज्ञात और मात्रक लिखना
C. केवल चित्र रंगना
D. फॉर्मूला बिना पढ़े रटना
View the correct answer
Correct option: B — ज्ञात-अज्ञात और मात्रक लिखना
NCERT numericals मात्रक और अज्ञात साफ चाहती हैं।
Q.19MCQLinear Equations in One Variable
Linear Equations in One Variable में गलत सर्वसमिका/सूत्र चुनें।
A. जाँच के लिए छोटी संख्या रखें
B. दोनों पक्ष बराबर होने चाहिए
C. किसी भी दो पद जोड़कर नया सूत्र बना लें
D. मात्रक दोनों पक्षों पर समान
View the correct answer
Correct option: C — किसी भी दो पद जोड़कर नया सूत्र बना लें
मनगढ़ंत सूत्र Class 8 पेपर काटते हैं।
Q.20MCQLinear Equations in One Variable
Linear Equations in One Variable अनुप्रयोग: 108 का 14% = ?
A. 94
B. 15
C. 122
D. 14
View the correct answer
Correct option: B — 15
108×14/100 = 15। प्रतिशत Comparing Quantities से पूरे गणित में चलता है।
