9th Standard Syllabus & Materials
9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -கற்கண்டு (இலக்கணம்) - தொடர் இலக்கணம், ஆகுபெயர் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -விரிவானம் (துணைப்பாடம்) - தாய்மைக்கு வறட்சி இல்லை! Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -கவிதை பேழை (செய்யுள்) - மார்கழி பெருவிழா Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உயிருக்கு வேர்-இலக்கணம் - பகுபத உறுப்பிலக்கணம் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil அமுதென்று பேர் - இலக்கணம்-எழுத்து -அளபெடை Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil அமுதென்று பேர்-துணைப்பாடம் - ஆறாம்திணை Important Questions And Answers Study Material - QB365 Set A

Published on: 20/02/2019
3rd Term Complete Study Material
Download Tamil Nadu 9th Standard Maths question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.
Questions + Answers key
Take MCQ Maths Test1.
In a football match, a goalkeeper of a team can stop the goal, 32 times out of 40 attempts tried by a team. Find the probability that the opponent team can convert the attempt into a goal.
2.
Two dice are rolled, find the probability that the sum is
(i) equal to 1
(ii) equal to 4
(iii) less than 13

3.
Find the area of a right triangle whose hypotenuse is 10cm and one of the acute angle is 24024'
4.
The adjacent sides of a parallelogram measures 34 m, 20 m and the measure of the diagonal is 42 m. Find the area of parallelogram.
5.
A land is in the shape of rhombus. The perimeter of the land is 160 m and one of the diagonal is 48 m. Find the area of the land.
6.
Two numbers are in the ratio 5:6. If 8 is subtracted from each of the numbers, the ratio becomes 4:5. Find the numbers.
7.
A boy standing at a point O finds his kite flying at a point P with distance OP = 25 m. It is at a height of 5m from the ground. When the thread is extended by 10 m from P, it reaches a point Q. What will be the height QN of the kite from the ground? (use trigonometric ratios)

8.
Find the coordinates of the point which divides the line segment joining A(−5,11) and B(4,−7) in the ratio 7:2.
9.
The points A(−3, 6), B(0, 7) and C(1, 9) are the mid-points of the sides DE, EF and FD of a triangle DEF. Show that the quadrilateral ABCD is a parallellogram.
10.
Solve the following linear equations
(i) \(\frac { 2(x+1) }{ 3 } =\frac { 3(x-2) }{ 5 } \)
(ii) \(\frac { 2 }{ x+1 } =4-\frac { x }{ x+1 } ,(x\neq -)\)
11.
In a recent year, of the 1184 centum scorers in various subjects in tenth standard public exams, 233 were in mathematics. 125 in social science and 106 in science. If one of the student is selected at random, find the probability of that selected student,
(i) is a centum scorer in Mathematics
(ii) is not a centum scorer in Science
12.
Team I and Team II play 10 cricket matches each of 20 overs. Their total scores in each match are tabulated in the table as follows:
| Match numbers | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| Team I | 200 | 122 | 111 | 88 | 156 | 184 | 99 | 199 | 121 | 156 |
| Team II | 143 | 123 | 156 | 92 | 164 | 72 | 100 | 201 | 98 | 157 |
What is the relative frequency of Team I winning?
13.
Two identical cubes of side 7 cm are joined end to end. Find the Total and Lateral surface area of the new resulting cuboid.
14.
The length, breadth and height of a hall are 25 m, 15 m and 5 m respectively. Find the cost of renovating its floor and four walls at the rate of Rs. 80 per m2.
15.
Find the value of sin 64034'.
16.
(i) If cosec A = sec 340, then find A
(ii) If tan B = cot 470, then find B.
17.
Express
(i) sin 74° in terms of cosine
(ii) tan 12° in terms of cotangent
(iii) cosec 39° in terms of secant
18.
The lengths of sides of a triangular field are 28 m, 15 m and 41 m. Calculate the area of the field. Find the cost of levelling the field at the rate of Rs. 20 per m2
19.
Solve 2x + 3y = 14 and 3x − 4y = 4 by the method of elimination.
20.
If the centroid of a triangle is at (−2, 1) and two of its vertices are (1, −6) and (−5, 2), then find the third vertex of the triangle.
21.
Check whether (5, −1) is a solution of the simultaneous equations x – 2y = 7 and 2x + 3y = 7.
22.
Solve for x and y: 8x − 3y = 5xy, 6x − 5y = −2xy by the method of elimination.
23.
In what ratio does the point P(–2, 4) divide the line segment joining the points A(–3, 6) and B(1, –2) internally?
24.
The volume of a cuboid is 660 cm3 and the area of the base is 33 cm2. Its height is _______.
10 cm
12 cm
20 cm
22 cm
25.
The lateral surface area of a cube of side 12 cm is _______.
144 cm2
196 cm2
576 cm2
664 cm2
26.
Probability lies between _______.
−1 and +1
0 and 1
0 and n
0 and \(\infty \)
27.
A number between 0 and 1 that is used to measure uncertainty is called _______.
Random variable
Trial
Simple event
Probability
28.
The value of \(\frac { sin{ 29 }^{ 0 }31' }{ cos{ 60 }^{ 0 }29' } \) is
0
2
1
-1
29.
The value of tan72° tan18° is ________.
0
1
180
720
30.
If \(\frac { { a }_{ 1 } }{ { a }_{ 2 } } \neq \frac { { b }_{ 1 } }{ { b }_{ 2 } } \) where a1x + b1y + c1 = 0 and a2x + b2 y + c2 = 0 then the given pair of linear equation has _______ solution(s)
no solution
two solutions
unique
infinite
31.
If (2,3) is a solution of linear equation 2x + 3y = k then, the value of k is _______.
12
6
0
13
32.
If the coordinates of the mid-points of the sides AB, BC and CA of a triangle are (3, 4), (1, 1) and (2, −3) respectively, then the vertices A and B of the triangle are ______.
(3, 2), (2, 4)
(4, 0), (2, 8)
(3, 4), (2, 0)
(4, 3), (2, 4)
33.
The coordinates of the point C dividing the line segment joining the points P(2, 4) and Q(5, 7) internally in the ratio 2:1 is______.
\((\frac{7}{2},\frac{11}{2})\)
(3, 5)
(4, 4)
(4, 6)
1.
Total no. of attempts n(S) = 40
Total no. of attempts by A team n(A) = 32
Total no. of attempts by the opponent team B = n(B) = 40 - 32 = 8
P(B) = \(\frac { n(B) }{ n(S) } =\frac { 8 }{ 40 } =\frac { 1 }{ 5 } \).
2.
When two dice are rolled
Sample space
S = {(1,1), (1,2), (1,3), (1,4), (1,5), (1,6), (2,1), (2,2), (2,3), (2,4), (2,5), (2,6), (3,1), (3,2), (3,3), (3,4), (3,5), (3,6), (4,1), (4,2), (4,3), (4,4),(4,5),(4,6), (5,1), (5,2), (5,3), (5,4), (5,5), (5,6), (6,1), (6,2), (6,3), (6,4), (6,5), (6,6)}
n(S) = 36
(i) Event of the sum is equal to 1 = 0
∴ Probability = \(\frac { 0 }{ n(S) } \) = 0
(ii) Event of the sum is equal to 4
B = {(1, 3), (2, 2), (3, 1)}
n(B) = 3
P(B)= \(\frac { n(B) }{ n(S) } =\frac { 3 }{ 6 } =\frac { 1 }{ 12 } \)
(iii) Event of the sum is equal to less than 13
C= {(1,1), (1,2), (1,3), (1,4), (1,5), (1,6), (2,1), (2,2), (2,3), (2,4), (2,5), (2,6), (3,1), (3,2), (3,3), (3,4), (3,5), (3,6), (4,1), (4,2), (4,3), (4,4), (4,5), (4,6), (5,1), (5,2), (5,3), (5,4), (5,5), (5,6), (6,1), (6,2), (6,3), (6,4), (6,5), (6,6)}
n(C) = 36
P(C) = \(\frac { n(C) }{ n(S) } =\frac { 36 }{ 6 } \).
3.

Hypotenuse = 10 cm
One of the acute angle = 24° 24'
sin 24° 24' = 0.4131'
\(\cfrac { x }{ 10 } =0.4131\)
x = 0.4131 \(\times\) 10
x = 4.131
cos 24° 24' = 0.9107
\(\cfrac { y }{ 10 } =0.9107\)
y = 9.107
\(\therefore\) Area of the triangle = \(\cfrac { 1 }{ 2 } bh\)
= \(\cfrac { 1 }{ 2 } \times y\times x\)
\(=\cfrac { 1 }{ 2 } \times 9.107\times 4.131=18.81sq.cm\)
4.
Area of the parallelogram = 2 \(\times\) Area of the Δ ABC
s = \(\frac { 34+20+42 }{ 2 } =\frac { 96 }{ 2 } \) = 48 m
Area of Δ ABC =\(\sqrt { 48(48-34)(48-20)(48-42) } \)
=\(\sqrt { 48\times 14\times 28\times 6 } =\sqrt { 112896 } \)= 336 m2
∴ Area of the parallelogram = 2 \(\times\) 336 m2 = 672 m2.

5.
Perimeter of the rhombus land = 160 m
4a = 160 m
a = 40 m
One of the diagonal = 48 m
∴ Area of the land = 2 \(\times\) Area of the Δ ABC
s = \(\frac { 40+40+48 }{ 2 } =\frac { 128 }{ 2 } \)= 64 m
Area of Δ ABC =\(\sqrt { s(s-a)(s-b)(s-c) } \)
=\(\sqrt { 64(64-40)(64-40)(64-48) } \)
=\(\sqrt { 64\times 24\times 24\times 16 } =\sqrt { 589824 } \)
= 768 m2
∴ Area of the land = 2 \(\times\) 768 m2 = 1536 m2


6.
\(\cfrac { x }{ y } =\cfrac { 5 }{ 6 } \)
\(\Rightarrow\) 6x = 5y
6x - 5y = 0 .......(1)
\(\cfrac { x-8 }{ y-8 } =\cfrac { 4 }{ 5 } \)
\(\Rightarrow\) 5(x - 8) = 4(y - 8)
5x-40 = 4y-32
5x -4y = 40 - 32
5x - 4y = 8 ------ (2)
(1) x 5 \(\Rightarrow\) 30x-25y = 0
(2) x 6 \(\Rightarrow\) \(\cfrac { 30x-24y=48 }{ -y=-48 } \) ...(2)
Substitute y = 48 in (1)
6x- 5(48) = 0
6x-240 = 0
6x = 240
\(x=\cfrac { 240 }{ 6 } =40\)
y = 48
\(\cfrac { x }{ y } =\cfrac { 40 }{ 48 } =\cfrac { 5 }{ 6 } \)
\(\therefore\) The number are in the Ratio 5 : 6
7.
In the figure,
\(\triangle\)OPM, \(\triangle\)OQN are similar triangles. In similar triangles the sides are in the same proportional.
\(\cfrac { QN }{ PM } =\cfrac { QO }{ PO } \)
\(\cfrac { h }{ 5 } =\cfrac { 35 }{ 25 } \)
\(h=\cfrac { 5\times 35 }{ 25 } \)

h = 7m
8.

x1 y1
Here (-5,11)
x2 y2
(4,-7)
m n
7 : 2
\(=P(x,y)\left( \frac { { mx }_{ 2 }+{ nx }_{ 1 } }{ m+n } ,\frac { { my }_{ 2 }+{ ny }_{ 1 } }{ m+n } \right) \)
\(=\left( \frac { 7\times 4+2\times -5 }{ 7+2 } ,\frac { 7\times -7+2\times 11) }{ 7+2 } \right) \)
\(=\left( \frac { 28-10 }{ 9 } ,\frac { -49+22 }{ 9 } \right) \)
\(=\left( \frac { 18 }{ 9 } ,\frac { -27 }{ 9 } \right) =(2,-3)\)
9.
In a parallelogram diagonals bisect each other and diagonals are not equal.
Mid point of DE \(=\left( \frac { { x }_{ 1 }+{ x }_{ 2 } }{ 2 } ,\frac { { y }_{ 1 }+{ y }_{ 2 } }{ 2 } \right) \)
(-3, 6)\(=\left( \frac { { x }_{ 1 }+{ x }_{ 2 } }{ 2 } ,\frac { { y }_{ 1 }+{ y }_{ 2 } }{ 2 } \right) \)
\(\frac { x_{ 1 }+{ x }_{ 2 } }{ 2 } =-3\ \ \ \ \ \frac { y_{ 1 }+y_{ 2 } }{ 2 } =6\)
x1 + x2 = -6........(1)
y1 + y2 = 12.......(2)
Mid point of EF\(\left( \frac { { x }_{ 2 }+{ x }_{ 3 } }{ 2 } ,\frac { { y }_{ 2 }+{ y }_{ 3 } }{ 2 } \right) \)
(0, 7)=\(\left( \frac { { x }_{ 2 }+{ x }_{ 3 } }{ 2 } ,\frac { { y }_{ 2 }+{ y }_{ 3 } }{ 2 } \right) \)
\(\frac { x_{ 2 }+{ x }_{ 3 } }{ 2 } =0\ \ \ \frac { y_{ 2 }+{ y }_{ 3 } }{ 2 } =7\)
x2+x3= 0..............(3)
Mid point of FD=\(\left( \frac { { x }_{ 3 }+{ x }_{ 1 } }{ 2 } ,\frac { { y }_{ 3 }+{ y }_{ 1 } }{ 2 } \right) =(-3,-2)\)
x3 + x1 = -6.......(5)
y3 + y1 = -4..........(6)

∴ D (x1, y1) = (-6, -3)
Mid points of the diagonals are equal in parallelogram
∴ We have to prove this
Mid point of AC \(=\left( \frac { (-3)+(-3) }{ 2 } ,\frac { 6+(-2) }{ 2 } \right) =\left( \frac { -6 }{ 2 } ,\frac { 4 }{ 2 } \right) =(-3,2)\)
Mid Point of BD \(=\left( \frac { -6+0 }{ 2 } ,\frac { -3+7 }{ 2 } \right) =\left( \frac { -6 }{ 2 } ,\frac { 4 }{ 2 } \right) =(-3,2)\)
∴ Mid point of AC = Mid point of BD
∴ ABCD is a parallelogram
10.
(i) \(\cfrac { 2x+2 }{ 3 } =\cfrac { 3x-6 }{ 5 } \)
5(2x+2) = 3(3x - 6) [By cross multiplication]
10x + 10 = 9x - 18
10x = 9x - 18 - 10
10x = 9x-28
10x- 9x = -28
x = -28
(ii)

2 = 4 (x + 1)-x
2 = 4x+4-x
3x + 4 = 2'
3x+4-4 = 2-4
3x =-2

11.
Total number of centum scorers = 1184
Therefore n = 1184
(i) Let E1 be the event of getting a centum scorer in Mathematics.
Therefore n(E1) = 233, That is, r1 = 233
\(P({ E })_{ 1 }=\frac { { r }_{ 2 } }{ n } =\frac { 233 }{ 1184 } \)
(ii) Let E2 be the event of getting a centum scorer in Science.
Therefore n(E2 ) = 106, That is, r2 = 106
\(P({ E })_{ 2 }=\frac { { r }_{ 2 } }{ n } =\frac {106 }{ 1184 } \)
P(E'2) = 1− P(E2)
\(=1-\frac { 106 }{ 1184 } \)
\(=\frac { 1078 }{ 1184 } \)
12.
In this experiment, each trial is a match where Team I faces Team II.
We are concerned about the winning status of Team I.
There are 10 trials in total; out of which Team I wins in the 1st, 6th and 9th matches.
The relative frequency of Team I winning the matches = \(\frac { 3 }{ 10 } \)or 0.3
13.
Side of a cube = 7 cm
Now length of the resulting cuboid (l) = 7+7 =14 cm
Breadth (b) = 7 cm, Height (h) = 7 cm
So, Total Surface Area = 2(lb + bh + lh)
= 2[(14 \(\times\) 7)+(7 \(\times\) 7)+(14 \(\times\) 7)]
= 2(98 + 49 + 98)
= 2 × 245
= 490 cm2
Lateral Surface Area = 2(l + b) × h
= 2(14 + 7) × 7 = 2 × 21× 7
= 294 cm2
14.
Here, length (l) = 25 m, breadth (b) =15 m, height (h) = 5 m.
Area of four walls = LSA of cuboid
= 2(l + b) × h
= 2(25 +15) × 5
= 80 × 5 = 400 m2
Area of the floor = l × b
= 25 ×15
= 375 m2
Total renovating area of the hall = (Area of four walls + Area of the floor) = (400 + 375) m2 = 775 m2
Therefore, cost of renovating at the rate of Rs.80 per m2 = 80 × 775
= Rs. 62,000
15.
| 0' | 6' | 12' | 18' | 24' | 30' | 36' | 42' | 48' | 54' | Mean Difference | |||||
| 0.00 | 0.10 | 0.20 | 0.30 | 0.40 | 0.50 | 0.60 | 0.70 | 0.80 | 0.90 | 1 | 2 | 3 | 4 | 5 | |
| 640 | 0.9026 | 5 | |||||||||||||
write 64034' = 64030' + 4'
From the table we have, sin64030' = 0.9026
16.
(i) We know that cosec A = sec(900 A)
sec(900 - A) sec(340)
900 - A =340
We get A = 90° − 34°
A = 560
(ii) We know that tan B = cot(900 - B)
cot(900 - B) = cot 470
900 - B = 470
We get B = 90° − 47°
B = 430
17.
(i) sin74° = sin(900 -160) (since, 900 -160 = 740 )
RHS is of the form sin(900 - \(\theta\)) = cos\(\theta\)
Therefore sin74° = cos160
(ii) tan12° = tan(900 - 780) (since, 120= 900 = 780 )
RHS is of the form tan(900- \(\theta\)) = cot \(\theta\)
Therefore tan12° = cot 780
(iii) cosec 39° = cosec(900 - 510) (since, 390 = 900 - 510 )
RHS is of the form cosec(900 - \(\theta\)) = sec\(\theta\)
Therefore cosec39° = sec510
18.
Let a = 28 m, b = 15 m and c = 41 m
Then, s = \(\frac{a+b+c}{2}=\frac{28+15+41}{2}=\frac{84}{2}\) = 42m
Area of triangular field =\(\sqrt { s(s-a)(s-b)(s-c) } \)
=\(\sqrt { 42(42-28)(42-15)(42-41) } \)
=\(\sqrt { 42\times 14\times 17\times 1 } \)
=\(\sqrt { 2\times 3\times 7\times 7\times 2\times 3\times 3\times 3\times 1 } \)
\(=2 \times 3 \times 7 \times 3\)
= 126 m2
Given the cost of levelling is Rs. 20 per m2.
The total cost of levelling the field = 20 \(\times\)126 = Rs. 2520.
19.
Given, 2x + 3y = 14 ...(1)
3x − 4y = 4 ...(2)
To eliminate y:
| Multiply (1) by 4, to get | 8x + 12y = 56 |
| Multiply (2) by 3, to get | 9x –12y = 12 |
| Adding, we get | 17x = 68 |
Therefore, x = 4
Substitute x = 4 in (1) to get 2x + 3y = 14
2(4) + 3y = 14
8 + 3y = 14
y = 2
Thus the solution is x = 4, y = 2.
Verification :
2x+3y = 14 ...(1)
2(4)+3(2) = 14
8 + 6 = 14
14 = 14 True
3x – 4y = 4 ...(2)
3(4) – 4(2) = 4
12 – 8 = 4
4 = 4 True
20.
Let the vertices of a triangle be A(1, −6), B(−5, 2) and C(x3, y3)
Given the centroid of a triangle as (−2, 1) we get,
\(\frac { { x }_{ 1 }+{ x }_{ 2 }+{ x }_{ 3 } }{ 3 } \) = -2
\(\frac { 1-5+{ x }_{ 3 } }{ 3 } \) = -2
−4 + x3 = −6
x3 = −2
\(\frac { { y }_{ 1 }+{ y }_{ 2 }+{ y }_{ 3 } }{ 3 } \) = 1
\(\frac { 6+2+{ y }_{ 3 } }{ 3 } \) = 1
−4 + y3 = 3
y3 = 7
Therefore, third vertex is (−2, 7).
21.
Given x – 2y = 7 …(1)
2x + 3y = 7 …(2)
When x = 5, y = −1 we get
From (1) x – 2y = 5 – 2(−1) = 5 + 2 = 7 which is RHS of (1)
From (2) 2x + 3y = 2(5) + 3(−1) = 10−3 = 7 which is RHS of (2)
Thus the values x = 5, y = −1 satisfy both (1) and (2) simultaneously. Therefore (5,−1) is a solution of the given equations.
22.
The given system of equations are 8x − 3y = 5xy ...(1)
6x − 5y = −2xy ...(2)
Observe that the given system is not linear because of the occurrence of xy term. Also note that if x =0, then y =0 and vice versa. So, (0,0) is a solution for the system and any other solution would have both x \(\neq \) 0 and y \(\neq \) 0
Let us take up the case where x \(\neq \) 0 and y \(\neq \) 0
Dividing both sides of each equation by xy,
\(\frac { 8x }{ xy } -\frac { 3y }{ xy } =\frac { 5xy }{ xy } \)
\(\frac { 6x }{ xy } -\frac { 5y }{ xy } =\frac { -2xy }{ xy } \)
Let \(a=\frac { 1 }{ x } ,b=\frac { 1 }{ y } \)
We get, \(\frac { 8 }{ y } -\frac { 3 }{ x } =5\) .....(3)
\(\frac { 6 }{ y } -\frac { 5 }{ x } =-2\) .......(4)
(3)&(4) respectively become, 8b − 3a = 5 ...(5)
b − 5a = −2 ...(6)
which are linear equations in a and b.
To eliminate a, we have, (5) \(\times\) 5\(\Rightarrow\) 40b −15a = 25 .....(7)
(6) × 3\(\Rightarrow\) 18b −15a = −6 .....(8)
Now proceed as in the previous example to get the solution\(\left( \frac { 11 }{ 23 } ,\frac { 22 }{ 31 } \right) \).
Thus, the system have two solutions \(\left( \frac { 11 }{ 23 } ,\frac { 22 }{ 31 } \right) \) and (0,0).
23.
Given points are A(–3, 6) and B(1, –2), P(–2, 4) divide AB internally in the ratio m : n.
By section formula,
\(P(x, y)=P\left(\frac{m x_{2}+n x_{1}}{m+n}, \frac{m y_{2}+n y_{1}}{m+n}\right)\)
= P(−2, 4) .......(1)
Here x1 = −3, y1 = 6, x2 = 1, y2 = −2
\((1)\Rightarrow \left( \frac { m(1)+n(-3) }{ m+n } ,\frac { m(-2)+n(6) }{ m+n } \right) \)
Equating x-coordinates, we get
\(\frac{m-3 n}{m+n}=-2\) or m− 3n = −2m− 2n
3m = n
\(\frac{m}{n}=\frac{1}{3}\)
m : n = 1: 3
Hence P divides AB internally in the ratio 1 : 3.
24.
(c)
20 cm
25.
(c)
576 cm2
26.
(b)
0 and 1
27.
(d)
Probability
28.
(c)
1
29.
(b)
1
30.
(c)
unique
31.
(d)
13
32.
(b)
(4, 0), (2, 8)
33.
(d)
(4, 6)
9th Standard Syllabus & Materials
9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - திருக்குறள் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - மணிமேகலை Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - ஏறு தழுவுதல் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உயிருக்கு வேர் - தண்ணீர் Important Questions And Answers Study Material - QB365 Set A
Tamilnadu Stateboard 9th Standard Subjects
Tamilnadu Stateboard Standards