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Q1
mcq
1 mark
The degree of the cubic polynomial is
Correct Answer: C —
Solution
By definition, the degree of a polynomial is the highest power of the variable present in it. A cubic polynomial is of the form $ax^3 + bx^2 + cx + d$ where $a \neq 0$. The highest power is 3.
Q2
mcq
1 mark
The discriminant of the quadratic equation $ax^2 + bx + c = 0$ is
-
A.
$b^2 - 4ac$
-
B.
$c^2 - 4ab$
-
C.
$b^2 + 4ac$
-
D.
$a^2 + 4ab$
Correct Answer: A —
Solution
For any quadratic equation $ax^2 + bx + c = 0$, the discriminant is defined as $D = b^2 - 4ac$.
Q3
mcq
1 mark
$(\sec^2 A - 1)$ is equal to
-
A.
$\tan^2 A$
-
B.
$\cot^2 A$
-
C.
$\sin^2 A$
-
D.
$\text{cosec}^2 A$
Correct Answer: A —
Solution
From the trigonometric identity $1 + \tan^2 A = \sec^2 A$, it follows that $\sec^2 A - 1 = \tan^2 A$.
Q4
mcq
1 mark
$7 \times 11 \times 13 + 13$ is a
-
A.
Prime number
-
B.
Composite number
-
C.
Irrational number
-
D.
Odd number
Correct Answer: B —
Solution
$7 \times 11 \times 13 + 13 = 13(7 \times 11 + 1) = 13(77 + 1) = 13 \times 78$. Since the number has factors other than 1 and itself (it is the product of 13 and 78), it is a composite number.
Q5
mcq
1 mark
If the pair of lines represented by linear equations $x + ky = 4$ and $2x + 4y = 12$ are parallel lines then the value of ‘k’ is
-
A.
$- 2$
-
B.
2
-
C.
4
-
D.
$- 4$
Correct Answer: B —
Solution
For lines $a_1x + b_1y + c_1 = 0$ and $a_2x + b_2y + c_2 = 0$ to be parallel, the condition is $\frac{a_1}{a_2} = \frac{b_1}{b_2} \neq \frac{c_1}{c_2}$. Here, $\frac{1}{2} = \frac{k}{4}$. Solving for $k$, we get $k = \frac{4}{2} = 2$.
Q6
mcq
1 mark
In the figure $DE \parallel BC$. If $AD = x, BD = y, AE = m$ and $CE = n$, then the correct relation among the following is
-
A.
$\frac{x}{y} = \frac{m}{m + n}$
-
B.
$\frac{x}{y} = \frac{n}{m}$
-
C.
$\frac{x + y}{x} = \frac{m}{m + n}$
-
D.
$\frac{x}{x + y} = \frac{m}{m + n}$
Q7
mcq
1 mark
In the figure $XY$ is a tangent to the circle with centre ‘O’. If $\angle AOB = 130^\circ$, then the measure of $\angle BAY$ is
-
A.
$90^\circ$
-
B.
$25^\circ$
-
C.
$50^\circ$
-
D.
$65^\circ$
Q8
mcq
1 mark
The formula to find the curved surface area of a frustum of a cone in the given figure is
-
A.
$A = \pi l (r_1 - r_2)$
-
B.
$A = \pi (r_1 + r_2) l + \pi r_1^2$
-
C.
$A = \pi l (r_1 + r_2)$
-
D.
$A = \frac{1}{3} \pi h (r_1^2 + r_2^2 + r_1 r_2)$
Q9
short answer
1 mark
Write the formula to find the $n^{th}$ term of the arithmetic progression with first term ‘a’ and common difference ‘d’.
Q10
short answer
1 mark
If the product of zeroes of the polynomial $f(x) = 2x^2 - 3x + k$ is 3, then find the value of ‘k’.
Q11
short answer
1 mark
A person buys 3 bats and 2 balls by paying Rs. 960. If a bat costs Rs. 300, then find the cost of one ball.
Q12
short answer
1 mark
If $P(A) = 80\%$ then show that the probability of not A is $\frac{1}{5}$.
Q13
short answer
1 mark
Write the formula to find the volume of a sphere having radius ‘r’ units.
Q14
short answer
1 mark
Express the denominator of $\frac{17}{40}$ in the form $2^m \times 5^n$ and find the value of ‘n’.
Q15
short answer
1 mark
Find the value of $\text{cosec}(90^\circ - \theta) \times \cos \theta$.
Q16
short answer
1 mark
If $\sin \theta = 1$, then find the value of $\cos \theta$.
Q17
long answer
2 marks
Prove that $2 + \sqrt{3}$ is an irrational number. OR Find the H.C.F. and L.C.M. of 3, 8 and 15.
Q17
short answer
2 marks
Prove that $2 + \sqrt{3}$ is an irrational number.
Q18
long answer
2 marks
Solve the given pair of linear equations by Elimination method: $x + 2y = 5$, $x - y = 2$.
Q19
long answer
2 marks
Find the sum of first 20 terms of the arithmetic progression 2, 5, 8, .... using formula.
Q20
long answer
2 marks
Find the roots of the equation $x^2 - 3x + 1 = 0$ using ‘quadratic formula’.
Q21
long answer
2 marks
If $\frac{\sqrt{3} \sec A}{\text{cosec} A} = 1$, then find the value of A. OR Prove that : $\sin 30^\circ \cdot \cos 60^\circ + \cos 30^\circ \cdot \sin 60^\circ = \sin 90^\circ$.
Q21
short answer
2 marks
If $\frac{\sqrt{3} \sec A}{\text{cosec} A} = 1$, then find the value of $A$.
Q22
long answer
2 marks
Find the coordinates of the point which divides the line segment joining the points $(-1, 7)$ and $(4, -3)$ internally in the ratio $2:3$.
Q23
short answer
3 marks
A bag contains cards bearing the numbers 2, 4, 8, 16, 32, 64, 128 and 256. One card is drawn at random from the bag. Find the probability that the card bears a perfect cube number.
Q24
short answer
2 marks
Find the H.C.F. and L.C.M. of 3, 8 and 15.
Q24
short answer
3 marks
Draw a circle of radius 3 cm and construct a pair of tangents to the circle such that the angle between them is 70°.
Q25
short answer
3 marks
Divide $p(x) = x^3 – 3x^2 + 3x – 5$ by $g(x) = x^2 – x + 1$ and find the quotient $[ q(x) ]$ and remainder $[ r(x) ]$.
Q26
short answer
2 marks
Prove that : $\sin 30^\circ . \cos 60^\circ + \cos 30^\circ . \sin 60^\circ = \sin 90^\circ$
Q26
short answer
3 marks
A train travels 360 km at a uniform speed. If the speed had been 5 km/h more, it would have taken 1 hour less for the same journey. Find the speed of the train.
Q27
long answer
3 marks
Prove that “The lengths of tangents drawn from an external point to a circle are equal”.
Q28
short answer
3 marks
The mid-point of the line segment joining the points $A(x, 0)$ and $B(0, y)$ is $(4, 3)$. Find the length of AB.
Q29
short answer
3 marks
Find the mean for the following data :
Class-interval Frequency
10 – 20 2
20 – 30 5
30 – 40 6
40 – 50 5
50 – 60 2
Q30
short answer
3 marks
During the medical check-up of 50 students of a class, their weights were recorded as follows. Draw a “more than type ogive” for the given data :
Weight ( in kg ) Number of students ( cumulative frequency )
20 or more than 20 50
25 or more than 25 40
30 or more than 30 25
35 or more than 35 20
40 or more than 40 10
45 or more than 45 5
Q31
short answer
3 marks
If the discriminant of the quadratic equation $x + \frac{1}{x} = \frac{10}{k}$ is zero, then find the value of ‘k’.
Q31
long answer
3 marks
In the figure, ABCD is a parallelogram. Point ‘P’ divides AB in the ratio 2 : 3 and ‘Q’ divides DC in the ratio 4 : 1. Prove that $OA = 2 \times OC$.
Q32
long answer
3 marks
Construct a triangle with sides 5 cm, 6 cm and 7 cm and then construct another triangle whose sides are $\frac{4}{3}$ of the corresponding sides of first triangle.
Q33
short answer
3 marks
The perimeter of a quadrant of a circle with centre ‘O’ is 25 cm. Find the area of the shaded region.
Q34
short answer
3 marks
Find the area of a triangle whose vertices are $A(5, 2)$, $B(4, 7)$ and $C(7, – 4)$.
Q34
long answer
4 marks
A person works in a shop from Monday to Saturday. His every-day earnings are in an arithmetic progression. His total earnings from Monday to Wednesday is Rs. 525 and Friday he gets Rs. 100 more than his Monday’s earning. Find his everyday’s earning.
Q35
long answer
4 marks
Find the solution of the given pair of linear equations by graphical method :
$x + y = 4$
$x + 2y = 6$
Q36
short answer
3 marks
Find the mode for the following data :
Class-interval Frequency
0 – 5 4
5 – 10 10
10 – 15 6
15 – 20 4
20 – 25 5
Q36
long answer
4 marks
There are two vertical towers on a level ground which are 300 m apart. A soldier in an helicopter above the ground observes the top of the towers and he found the angles of depression to be 60° and 30° as shown in the figure. If the height of the taller tower is 500 m and the distance between the foot of the shorter tower and the foot of the altitude from the helicopter to the ground is $100\sqrt{3} \text{ m}$, then find the height of the shorter tower. [ Take $\sqrt{3} = 1.73$ ]
Q37
long answer
4 marks
Prove that “In a right triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides”.
Q38
long answer
5 marks
The volume of a cylinder is equal to 5 times the volume of a cone. The base radius and slant height of the cone are 7 cm and 25 cm respectively. If the radius of the circular base of the cylinder is 14 cm, then find the volume and curved surface area of the cylinder.
Q41
short answer
3 marks
In the figure, diameters AB and CD intersect at ‘O’. If length of the arc $BC = 22 \text{ cm}$ and $\angle AOD = 60^\circ$, then find the area of the sector AOC.
Q43
long answer
4 marks
The angles of a quadrilateral are in arithmetic progression. If the sum of a pair of opposite angles is 130°, then find the angles of the quadrilateral.