The HCF of and is:
- (A)48
- (B)54
- (C)72
- (D)36
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20 questions, 1 mark each. MCQs (Q1 to Q18) and assertion-reason (Q19, Q20).
The HCF of and is:
The natural number 2 is:
Answer: (A) a prime number
Report an error on this questionFor any natural number , ends with the digit:
Answer: (B) 6
Report an error on this questionThe graph of is given. The number of zeroes of is:

Answer: (A) 0
Report an error on this questionIf a pair of linear equations in two variables is represented by two coincident lines, then the pair of equations has:
Answer: (D) an infinite number of solutions
Report an error on this questionThe common difference of the AP: is:
If and are similar such that and cm, then is equal to:
The mid-point of the line segment joining the points and lies on:
Answer: (A) -axis
Report an error on this questionGiven that , then is equal to:
If , then the value of is:
A car is moving away from the base of a m high tower. The angle of elevation of the top of the tower from the car at an instant, when the car is m away from the base of the tower, is:
If and are two tangents to a circle with centre from an external point so that , then is equal to:
Answer: (A)
Report an error on this questionIn the given figure, is a tangent from an external point to a circle with centre . If , then is equal to:

Answer: (D)
Report an error on this questionThe length of the arc of a sector of a circle with radius cm and of central angle is:
The hour hand of a clock is cm long. The angle swept by it between a.m. and a.m. is:
Answer: (C)
Report an error on this questionThe total surface area of a solid hemisphere of diameter is:
Answer: (A)
Report an error on this questionIf the mean and mode of a data are 12 and 21 respectively, then its median is:
A die is thrown once. Probability of getting a number other than 3 is:
Assertion (A): The probability that a leap year has Mondays is .
Reason (R): The probability that a non-leap year has Mondays is .
Answer: (C) A is true, R is false
Report an error on this questionAssertion (A): The polynomial has two zeroes.
Reason (R): A quadratic polynomial can have at most two zeroes.
Answer: (B) Both A and R are true, but R is not the correct explanation of A
Report an error on this question5 questions, 2 marks each.
If are the zeroes of the polynomial , then find the value of .
(a) In , . If , , and , then find the value of .
OR
(b) In the figure given, , with cm, cm, and , cm, cm. Find the values of and .

Answer: (a) (b) cm, cm
Report an error on this questionThe coordinates of the centre of a circle are . Find the value(s) of , if the circle passes through the point and has radius units.
Answer: or
Report an error on this question(a) If , then find the value of .
OR
(b) If , then find the value of .
Two concentric circles are of radii 5 cm and 4 cm. Find the length of the chord of the larger circle which touches the smaller circle.
Answer: cm
Report an error on this question6 questions, 3 marks each.
Prove that is an irrational number.
Answer: Proved
Report an error on this questionFind the ratio in which the -axis divides the line segment joining the points and . Also, find the point of intersection.
Answer: Ratio ; point
Report an error on this question(a) If , , then prove that .
OR
(b) Prove that .
(a) In the given figure, is a right triangle in which , cm and cm. Find the radius of the circle inscribed in the triangle .
OR
(b) In the given figure, if a circle touches the side of at and extended sides and at and respectively, then prove that .

Answer: (a) cm (b) proved
Report an error on this questionA solid is in the form of a cylinder with hemispherical ends. The total height of the solid is cm and the diameter of the cylinder is cm. Find the total volume of the solid. (Use )
Answer: cm³
Common mistake: Taking the cylinder as 20 − 7 = 13 only after adding the two radii. Using 20 cm or 20 − 3.5 for the cylinder overcounts.
Report an error on this questionTwo dice of different colours are thrown at the same time. Write down all the possible outcomes. What is the probability that:
(i) same number appears on both the dice?
(ii) different number appears on both the dice?
Answer: (i) (ii)
Report an error on this question4 questions, 5 marks each.
Determine graphically, the coordinates of vertices of a triangle whose equations are ; and . Also, find the area of this triangle.
Answer: Vertices , , ; area square units
Report an error on this question(a) A faster train takes one hour less than a slower train for a journey of km. If the speed of the slower train is km/hr less than that of the faster train, find the speeds of the two trains.
OR
(b) The sum of the areas of two squares is m². If the difference in their perimeters is m, find the sides of the two squares.
Answer: (a) km/h and km/h (b) m and m
Report an error on this question(a) State and prove Basic Proportionality Theorem.
OR
(b) In the given figure, and are respectively the medians of and . If , then prove that: (i) (ii) .

Answer: (a) proved (b) both proved
Report an error on this questionThe mean of the following frequency distribution is 35. Find the values of x and y, if the sum of frequencies is 25:
| Class | 0–10 | 10–20 | 20–30 | 30–40 | 40–50 | 50–60 | 60–70 |
|---|---|---|---|---|---|---|---|
| Frequency | 1 | x | 5 | 7 | y | 3 | 1 |
Answer: and
Report an error on this question3 case studies, 4 marks each.
Case study 1. In a potato race, a bucket is placed at the starting point, which is 5 m from the first potato. The other potatoes are arranged 3 m apart in a straight line, with a total of 10 potatoes. A competitor starts from the bucket, picks up the nearest potato, runs back to the bucket to drop it in, then returns to pick up the next potato. This process continues until all the potatoes are in the bucket.
Based on the above information, answer the following questions:
(i) What is the distance covered to pick up the first potato and drop it in bucket? [1]
(ii) What is the distance covered to pick up the second potato and drop it in bucket? [1]
(iii) (a) What is the total distance the competitor has to run? [2]
OR
(iii) (b) If average speed of competitor is 5 m/s, then find the average time taken by competitor to put all the potatoes in the bucket. [2]
Answer: (i) m (ii) m (iii)(a) m (iii)(b) s
Report an error on this questionCase study 2. Radio towers are used for transmitting a range of communication services including radio and television. The tower will either act as an antenna itself or support one or more antennas on its structure. On a similar concept, a radio station tower was built in two sections ‘A’ and ‘B’. Tower is supported by wires from a point ‘O’. Distance between the base of the tower and point ‘O’ is 6 m. From point ‘O’, the angle of elevation of the top of the section ‘B’ is 30° and the angle of elevation of the top of section ‘A’ is 60°.
Based on the above information, answer the following questions:
(i) Find the length of the wire from the point ‘O’ to the top of section ‘B’. [1]
(ii) Find the length of the wire from the point ‘O’ to the top of section ‘A’. [1]
(iii) (a) Find the distance AB. [2]
OR
(iii) (b) Find the area of △OPB. [2]

Answer: (i) m (ii) m (iii)(a) m (iii)(b) m²
Report an error on this questionCase study 3. A brooch is crafted from silver wire in the shape of a circle with a diameter of 35 cm. The wire is also used to create 5 diameters, dividing the circle into 10 equal sectors as shown in figure.
Based on the above information, answer the following questions:
(i) What is the radius of circle? [1]
(ii) What is the circumference of the brooch? [1]
(iii) (a) What is the total length of silver wire required? [2]
OR
(iii) (b) What is the area of each sector of the brooch? [2]
Answer: (i) cm (ii) cm (iii)(a) cm (iii)(b) cm²
Report an error on this questionQuestions are from the official CBSE paper. Figures are described in words; see the PDF for the originals. Solutions are written by CogniGuru.
Each chapter below is what the paper tested, with a one-minute animated lesson on the idea behind it.
Trigonometry
Q9, Q10, Q11, Q24, Q28, Q37 (12 marks): standard values and the identity sin² + cos² = 1.
How to remember trig values at 0°, 30°, 45°, 60°, 90° — Class 10Triangles
Q7, Q22, Q34 (8 marks): similarity criteria, matching angles by sides, and the Basic Proportionality Theorem.
Why are two equal angles enough to prove triangles similar (AA)? — Class 10Congruence vs Similarity — why equal angles alone prove nothingCircles
Q12, Q13, Q25, Q29 (7 marks): a tangent is perpendicular to the radius, and tangents from one point are equal.
Why is a tangent perpendicular to the radius? — Class 10Real Numbers
Q1, Q2, Q3, Q26 (6 marks): HCF and LCM, rational and irrational numbers, and proofs of irrationality.
Rational vs Irrational Numbers — is 22/7 actually equal to π?Why is √2 irrational? The proof — Class 10Linear Equations
Q5, Q32 (6 marks): solving a pair of equations, graphing it, and when a pair is consistent.
When do two linear equations have no solution? — Class 10Coordinate Geometry
Q8, Q23, Q27 (6 marks): the distance, mid-point and section formulas.
Why is the distance formula just Pythagoras? — Class 10Midpoint Formula vs Section Formula — Class 10Statistics
Q17, Q35 (6 marks): mean, median and mode of grouped data.
Mean vs Median vs Mode — why one outlier can lie to youArithmetic Progressions
Q6, Q36 (5 marks): the nth term and the sum of n terms.
Arithmetic vs Geometric Progression — why doubling always wins eventuallyProbability
Q18, Q19, Q31 (5 marks): favourable outcomes over total outcomes, and sure events.
Why is probability always between 0 and 1? — Class 10Quadratic Equations
Q33 (5 marks): the discriminant, standard form and solving by factorising.
Why does a quadratic have at most two real roots? — Class 10Polynomials
Q4, Q20, Q21 (4 marks): zeroes, their sum and product, and reading zeroes from a graph.
Why is the sum of zeroes −b/a and the product c/a? — Class 10Stuck on a step in any solution?
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The HCF of and is:
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