9th Standard Mathematics Questions and Answers from 2019

Preparing for your 9th standard mathematics exams can be challenging. Practicing past question papers helps you understand the exam pattern and improves your problem-solving skills. This compilation of questions and answers from the 2019 mathematics paper is designed to aid your studies and boost your confidence.

Mathematics Questions and Answers

Question: What is the value of 144\sqrt{144}144​?

Answer: The value of 144\sqrt{144}144​ is 12.

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Question: Solve for $x$ in the equation $2x+5=17$.

Answer: Subtracting 5 from both sides: $2x=12$. Dividing by 2: $x=6$.

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Question: What is the area of a triangle with base 10 cm and height 5 cm?

Answer: Area = 12×10×5=25\frac{1}{2} \times 10 \times 5 = 2521​×10×5=25 cm².

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Question: Simplify 34+25\frac{3}{4} + \frac{2}{5}43​+52​.

Answer: 1520+820=2320=1320\frac{15}{20} + \frac{8}{20} = \frac{23}{20} = 1 \frac{3}{20}2015​+208​=2023​=1203​.

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Question: If the perimeter of a square is 20 cm, what is the length of one side?

Answer: Each side = 204=5\frac{20}{4} = 5420​=5 cm.

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Question: Find the mean of the numbers 4, 8, 6, 10, and 2.

Answer: Mean = 4+8+6+10+25=305=6\frac{4 + 8 + 6 + 10 + 2}{5} = \frac{30}{5} = 654+8+6+10+2​=530​=6.

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Question: Convert 45 degrees to radians.

Answer: 45∘=π445^\circ = \frac{\pi}{4}45∘=4π​ radians.

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Question: What is the volume of a cube with edge length 3 cm?

Answer: Volume = 33=273^3 = 2733=27 cm³.

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Question: Solve the inequality $3x-7>2x+5$.

Answer: Subtract $2x$ from both sides: $x-7>5$. Add 7: $x>12$.

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Question: What is the probability of getting a head when flipping a fair coin?

Answer: The probability is 12\frac{1}{2}21​.

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Question: Find the slope of the line passing through points (2,3) and (4,7).

Answer: Slope m=7−34−2=42=2m = \frac{7-3}{4-2} = \frac{4}{2} = 2m=4−27−3​=24​=2.

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Question: Simplify $5(2x-3)-4x$.

Answer: $10x-15-4x=6x-15$.

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Question: What is the value of $\pi$ up to two decimal places?

Answer: $\pi \approx 3.14$.

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Question: Calculate the circumference of a circle with radius 7 cm. Use $\pi =22/7$.

Answer: Circumference = 2×227×7=442 \times \frac{22}{7} \times 7 = 442×722​×7=44 cm.

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Question: If $y=3x+4$, find $y$ when $x=5$.

Answer: $y=3(5)+4=19$.

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Question: Factorize x2−9x^2 – 9x2−9.

Answer: x2−9=(x+3)(x−3)x^2 – 9 = (x + 3)(x – 3)x2−9=(x+3)(x−3).

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Question: What is the next prime number after 7?

Answer: The next prime number after 7 is 11.

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Question: Calculate the simple interest on ₹5000 at 5% per annum for 3 years.

Answer: Simple Interest = 5000×5×3100=₹750\frac{5000 \times 5 \times 3}{100} = ₹7501005000×5×3​=₹750.

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Question: Find the perimeter of a rectangle with length 12 cm and breadth 8 cm.

Answer: Perimeter = $2\times (12+8)=40$ cm.

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Question: What is the square of 15?

Answer: 152=22515^2 = 225152=225.

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Question: Solve for $x$ in the equation $x/4=3$.

Answer: $x=3\times 4=12$.

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Question: Define a right-angled triangle.

Answer: A triangle with one angle equal to 90 degrees.

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Question: What is the decimal equivalent of 35\frac{3}{5}53​?

Answer: 35=0.6\frac{3}{5} = 0.653​=0.6.

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Question: Calculate the area of a rectangle with length 9 m and width 4 m.

Answer: Area = $9\times 4=36$ m².

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Question: What is the perimeter of a circle called?

Answer: The perimeter of a circle is called the circumference.

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Question: Find the value of $x$ if $7x=49$.

Answer: $x=7$.

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Question: What is the formula for the area of a circle?

Answer: Area = πr2\pi r^2πr2.

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Question: Convert 0.75 to a fraction.

Answer: 0.75=340.75 = \frac{3}{4}0.75=43​.

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Question: What is the highest common factor (HCF) of 12 and 18?

Answer: HCF of 12 and 18 is 6.

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Question: Solve for $y$ in the equation $2y+3=11$.

Answer: Subtract 3: $2y=8$. Divide by 2: $y=4$.

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Question: What is the term for a polygon with eight sides?

Answer: An octagon.

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Question: Calculate the area of a square with side length 6 cm.

Answer: Area = 62=366^2 = 3662=36 cm².

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Question: What is the perimeter of an equilateral triangle with side 5 cm?

Answer: Perimeter = $3\times 5=15$ cm.

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Question: Define the term ‘vertex’ in geometry.

Answer: A vertex is a corner point where two or more lines or edges meet.

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Question: What is the sum of the interior angles of a triangle?

Answer: The sum is 180 degrees.

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Question: Solve the equation $5x-2=3x+4$.

Answer: Subtract $3x$: $2x-2=4$. Add 2: $2x=6$. Divide by 2: $x=3$.

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Question: What is the product of $7$ and $8$?

Answer: The product is 56.

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Question: Find the value of $x$ in x2=64x^2 = 64x2=64.

Answer: $x=8$ or $x=-8$.

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Question: What is the reciprocal of 23\frac{2}{3}32​?

Answer: The reciprocal is 32\frac{3}{2}23​.

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Question: Calculate the perimeter of a parallelogram with sides 10 cm and 6 cm.

Answer: Perimeter = $2\times (10+6)=32$ cm.

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Question: What is the decimal form of 710\frac{7}{10}107​?

Answer: 710=0.7\frac{7}{10} = 0.7107​=0.7.

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Question: Solve for $x$: $9x=81$.

Answer: $x=9$.

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Question: What is the term for a four-sided polygon?

Answer: A quadrilateral.

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Question: Find the least common multiple (LCM) of 4 and 6.

Answer: LCM of 4 and 6 is 12.

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Question: What is the formula for calculating simple interest?

Answer: Simple Interest = Principal×Rate×Time100\frac{Principal \times Rate \times Time}{100}100Principal×Rate×Time​.

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Question: Convert 3/4 to a percentage.

Answer: 34=75%\frac{3}{4} = 75\%43​=75%.

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Question: What is the value of 828^282?

Answer: 82=648^2 = 6482=64.

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Question: Define ‘parallel lines’.

Answer: Lines in the same plane that never meet, no matter how far they are extended.

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Question: What is the sum of the first five natural numbers?

Answer: $1+2+3+4+5=15$.

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Question: Solve for $y$ in $y-7=14$.

Answer: $y=21$.

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Question: What is the area of a circle with diameter 10 cm? Use $\pi =3.14$.

Answer: Radius = 5 cm. Area = 3.14×52=78.53.14 \times 5^2 = 78.53.14×52=78.5 cm².

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Question: Find the value of $x$ in x5=9\frac{x}{5} = 95x​=9.

Answer: $x=45$.

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Question: What is the perimeter of a triangle with sides 7 cm, 10 cm, and 5 cm?

Answer: Perimeter = $7+10+5=22$ cm.

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Question: Simplify $4(a+3)-2a$.

Answer: $4a+12-2a=2a+12$.

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Question: What is the next number in the sequence: 2, 4, 6, 8, …?

Answer: The next number is 10.

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Question: Calculate the area of a trapezoid with bases 8 cm and 5 cm, and height 4 cm.

Answer: Area = 12×(8+5)×4=26\frac{1}{2} \times (8 + 5) \times 4 = 2621​×(8+5)×4=26 cm².

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Question: What is the value of 93\frac{9}{3}39​?

Answer: 93=3\frac{9}{3} = 339​=3.

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Question: Define ‘acute angle’.

Answer: An angle less than 90 degrees.

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Question: Solve the equation $6x=3x+12$.

Answer: Subtract $3x$: $3x=12$. Divide by 3: $x=4$.

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Question: What is the reciprocal of 5?

Answer: The reciprocal of 5 is 15\frac{1}{5}51​.

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Question: Find the perimeter of a rectangle with length 15 cm and width 7 cm.

Answer: Perimeter = $2\times (15+7)=44$ cm.

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Question: What is the square root of 81?

Answer: The square root of 81 is 9.

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Question: Calculate the mean of the following numbers: 2, 4, 6, 8, 10.

Answer: Mean = 2+4+6+8+105=6\frac{2 + 4 + 6 + 8 + 10}{5} = 652+4+6+8+10​=6.

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Question: What is the formula to calculate the perimeter of a circle?

Answer: Perimeter of a circle is called circumference, calculated as $2\pi r$.

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Question: Solve for $x$: $x+15=20$.

Answer: $x=5$.

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Mathematics is a fundamental subject that builds the foundation for various fields. Regular practice of questions and understanding their solutions enhance your analytical skills. Utilize these questions and answers to prepare effectively for your exams and achieve academic success.