Showing posts with label class9-maths. Show all posts
Showing posts with label class9-maths. Show all posts

Sunday 6 August 2017

CBSE Class 9 - Maths- Periodic Test Paper - (2016-17) (#cbsePapers)

CBSE Class 9 - Maths- Periodic Test Paper - (2016-17) (#cbsePapers)

CBSE Class 9 - Maths- Periodic Test Paper - (2016-17) 

Topics covered are:
1. Euclid Geometry
2. Co-ordinate Geometry
3. Lines and Angles




Sunday 30 July 2017

CBSE CLASS 9 - Maths - Heron's Formula - Assignment Sheet (#cbseNotes)

Heron's Formula

Assignment Sheet
CLASS 9 - Maths
CBSE CLASS 9 - Maths - Heron's Formula - Assignment Sheet (#cbseNotes)


The sides of a triangular field are 41 m,40 m and 9 m. Find the number of rose beds that can be prepared in the field, if each rose bed ,on an average needs 900 cm² space.


Find the cost of lying grass in a triangular field of sides 50m ,65 m, and 65 m at the rate of ₹ 7 per m²


From a point in the interior of an equilateral triangle, perpendiculars are drawn on the three sides. The lengths of the perpendiculars are 14 cm, 10cm and 6 cm. Find the area of the triangle.


The perimeter of an isosceles triangle is 32 cm. The ratio of the equal side to its base is 3:2. Find the area of the triangle.

Friday 12 May 2017

CBSE Class 9 - Maths - Co-Ordinate Geometry (Questions and Answers) (#cbseNotes)

Coordinate Geometry

Q & A


CBSE Class 9 - Maths - Co-Ordinate Geometry (Questions and Anwers) (#cbseNotes)


Q1: Write the name of the point where both axes intersect?

Answer: Origin


Q2: In which quadrant(s), ordinate of a point is negative?

Answer: III and IV


Q3: If the cooridnates of of two points P(-2,3) and Q(-3, 5), then find (abscissa of P) - (abscissa of Q) 

Answer: = (-2) - (-3) = -2 + 3 = 1

Monday 24 April 2017

CBSE Class 9 - Maths - Number Systems - Important Points To Remember (#cbsenotes)

Number Systems

CBSE Class 9 Maths 
Important Points To Remember
CBSE Class 9 - Maths - Number Systems - Important Points To Remember (#cbsenotes)

Counting numbers 1, 2, 3, 4... are called Natural Numbers (N)


Whole Numbers (W): Natural numbers 1, 2, 3... together with number 0 (zero) are called Whole Numbers


All natural numbers, zero and negative numbers together i.e. ...., –4, –3, –2, –1, 0, 1, 2, 3, 4, ... are known as Integers (Z).


Rational Numbers (Q): Numbers of the form p/q where p, q both are integers and q ≠ 0.


Tuesday 4 April 2017

CBSE Class 9 - Maths - Chapter 2 - Polynomials (Important Points) (#cbsenotes)

Polynomials

CBSE Class 9 - Maths - Chapter 2 - Polynomials (Important Points) (#cbsenotes)
(Important Points)
CBSE Class 9 - Maths Chapter 2

A combination of constants and variables which are connected by basic mathematical operations, is known as Algebraic Expression. For e.g. x² – 7x + 2, xy² – 3 etc.

② A Polynomials p(x) in one variable x is an algebric expression in x of the form
p(x) = anxn + an–1xn–1 + ... + a1 x + a0 , where a0 , a1 , a2 ..... an are constant and a n ≠ 0 are called coefficients and n is a positive integer.

The highest power of variable x in a polynomial p(x) is called the degree of the polynomial.

A polynomial of degree 1 is called a linear polynomial. For e.g. 4x + 9 is a linear polynomial in x.

Monday 27 March 2017

CBSE Class 9 - SA2 Mathematics Sample Question Paper (2016-17)(#cbsepapers)

CBSE Class 9 - SA2 Mathematics Sample Question Paper (2016-17)(#cbsepapers)

CBSE Class 9 - SA2 Mathematics Sample Question Paper (2016-17)





CBSE Class 9 - Mathematics - CH 14: Statistics - Important Points

Statistics - Important Points

CBSE Class 9 - Mathematics 
CBSE Class 9 - Mathematics - CH 14: Statistics - Important Points

In statistics we study collection, presentation analysis and interpretation of data.

Facts or figures collected with a definite purpose are called data.

Data are fundamental. Statistical tests are performed on raw not manipulated data.

The number of times an observation occurs in the given data is called frequency of the observation.

Class intervals are the groups in which all observations are divided.

Friday 17 February 2017

CBSE Class 8 - Maths - CH3 - Understanding Quadrilaterals (Worksheet) (#cbsenotes)

Understanding Quadrilaterals

CBSE Class 8 - Maths - CH3 - Understanding Quadrilaterals (Worksheet) (#cbsenotes)
(Worksheet)

The worksheet helps you identify a specific quadrilateral based on its properties.

☛Directions: Fill in the blanks

A simple closed curve made up of only line segments is called a ________.
 


A _________ of a polygon is a line segment connecting two non- consecutive vertices.
 


A _______ _______ is a polygon in which no portion of its any diagonal is in its exterior.
 


A quadrilateral is a polygon having only ________ sides.
 

Wednesday 15 February 2017

CBSE Class 9- Maths - Surface Areas and Volumes - NCERT EXERCISE 13.8 (#ncertsolutions) (#cbsenotes)

Surface Areas and Volumes - Spheres

CBSE Class 9- Maths - Surface Areas and Volumes - NCERT EXERCISE 13.8 (#ncertsolutions) (#cbsenotes)

Class 9 - Maths - NCERT EXERCISE 13.8


Q1: Find the volume of a sphere whose radius is

(i) 7 cm

(ii) 0.63 m


Answer:
(i) Given, r = 7 cm
Volume of sphere = (4/3)πr³
= (4/3) × (22/7) × (7)³
= 1437⅓ cm³

(ii) Given,  r = 0.63 m
Volume of sphere = (4/3)πr³
= (4/3) × (22/7) × (0.63)³
= 1.05 m³ (approx)



Monday 6 February 2017

CBSE Class 9- Maths - Surface Areas and Volumes -NCERT EXERCISE 13.7 (#cbsenotes)

Surface Areas and Volumes 
NCERT EXERCISE 13.7

CBSE Class 9- Maths - Surface Areas and Volumes -NCERT EXERCISE 13.7 (#cbsenotes)


Q1: Find the volume of the right circular cone with
(i) radius 6 cm, height 7 cm
(ii) radius 3.5 cm, height 12 cm

Answer:
(i) Given, r = 6 cm, h = 7 cm

 Volume of the cone = ⅓πr²h
= (1/3) × (22/7) × 6² × 7
= 264 cm³ (Answer)

(ii) Given, r = 3.5 cm, h = 12cm
 Volume of the cone = ⅓πr²h
  = (1/3) × (22/7) × 3.5² × 12
  = 154 cm³ (Answer)


Sunday 29 January 2017

CBSE Class 9 Maths - Surface Areas and Volumes - NCERT Exercise 13.6 (#cbsenotes) (#NCERTAnswers)

Surface Areas and Volumes (Cylinder)

EXERCISE 13.6
CBSE Class 9 Maths - Surface Areas and Volumes - NCERT Exercise 13.6 (#cbsenotes) (#NCERTAnswers)


Q1: The circumference of the base of a cylindrical vessel is 132 cm and its height is 25 cm. How many litres of water can it hold? (1000 cm³ = 1l)

Answer: Given, h = 25 cm, 2πr = 132 cm.
2πr = 132
2 × (22/7) × r = 132
r = (132 × 7)/ (2 × 22) = 21cm

Volume = πr²h = (22/7) × 21 × 21 × 25
= 34650 cm³
= 34650/1000
= 34.65 litres  (Answer)


Q2: The inner diameter of a cylindrical wooden pipe is 24 cm and its outer diameter is 28 cm. The length of the pipe is 35 cm. Find the mass of the pipe, if 1 cm³ of wood has a mass of 0.6 g.

Friday 27 January 2017

CBSE Class 9 Maths - Surface Areas and Volumes - NCERT Exercise 13.5 (#cbsenotes) (#ncertsolutions)

Surface Areas and Volumes 

NCERT Exercise 13.5
CBSE Class 9 Maths - Surface Areas and Volumes - NCERT Exercise 13.5 (#cbsenotes) (#ncertsolutions)


Q1: A matchbox measures 4 cm × 2.5 cm × 1.5 cm. What will be the volume of a packet containing 12 such boxes?

Answer: Given, l = 4 cm, b = 2.5 cm, h = 1.5 cm
Volume of 1 matchbox = lbh
= 4 × 2.5 × 1.5 cm3 = 15 cm³
Volume of 12 matchboxes = 15 × 12  = 180 cm³ (Answer)


Q2: A cuboidal water tank is 6 m long, 5 m wide and 4.5 m deep. How many litres of water can it hold? (1 m³ = 1000 l)

Answer: Given,  l = 6 m, b = 5 m, h = 4.5 m
Volume of the tank = lbh
= 6 × 5 × 4.5 = 135 m³
= 135 × 1000 litres = 1,35,000 litres (Answer)


Thursday 26 January 2017

CBSE Class 9 - Maths - Surface Areas and Volumes (NCERT Ex 13.4) (#cbseclass9notes)

Surface Areas and Volumes - Spheres
(NCERT Ex 13.4)

CBSE Class 9 - Maths - Surface Areas and Volumes (NCERT Ex 13.4) (#cbseclass9notes)


Q1: Find the surface area of a sphere of radius 
(i) 10.5 cm
(ii) 5.6 cm
(iii) 14 cm

Answer:
(i) r = 10.5 cm
Surface area of the sphere = 4πr²
= 4 × (22/7) × (10.5)²
  = 1386 cm² (Answer)

(ii) r = 5.6 cm
Surface area of the sphere = 4πr²
= 4 × (22/7) × (5.6)²
= 394.24 cm² (Answer)

(iii) r = 14 cm
Surface area of the sphere = 4πr²
= 4 × (22/7) × 14 × 14
= 2464 cm² (Answer)


Q2: Find the surface area of sphere of a diameter :
(i) 14 cm
(ii) 21 cm
(iii) 3.5 m

Tuesday 24 January 2017

CBSE Class 9 - Maths - Surface Areas and Volumes - NCERT Ex 13.3 (#cbsenotes)

Surface Areas and Volumes

CBSE Class 9 - Maths - Surface Areas and Volumes - NCERT Ex 13.3 (#cbsenotes)

EXERCISE 13.3

Q1: Diameter of the base of a cone is 10.5 cm and its slant height is 10 cm. Find its curved surface area.

Answer: Given r = 10.5/2 = 5.25 cm, l = 10 cm.

Curved surface area (CSA) of the cone = πrl
= (22/7) × 5.25 × 10  = 165 cm² (Answer)



Q2: Find the total surface area of a cone, if its slant height is 21 m and diameter of its base is 24 m.

Answer: Given, l = 21m, r = 24/2 = 12 m
TSA (cone) = πr(l + r)
= (22/7) × 12 (21 + 12)
= 1244.57 m² (Answer)


CBSE Class 9 Maths - Surface Areas and Volumes - NCERT Exercise 13.2 (#cbseclass9Notes)

Surface Areas and Volumes

CBSE Class 9 Maths - Surface Areas and Volumes - NCERT Exercise 13.2 (#cbseclass9Notes)

NCERT Exercise 13.2

Q1: The curved surface area of a right circular cylinder of height 14 cm is 88 cm². Find the diameter of the base of the cylinder.

Answer: Given, h = 14 cm,
curved, surface area (CSA) = 88 cm², r = ?
CSA  = 2πrh
88 = 2 × (22/7) × r × 14
88 = 44 × 2 × r
r = 88/88 = 1
diameter = 2r = 2 cm


Q2: It is required to make a closed cylindrical tank of height 1 m and base diameter 140 cm from a metal sheet. How many square metres of the sheet are required for the same?.

Sunday 22 January 2017

CBSE Class 9 Maths - SURFACE AREAS AND VOLUMES (NCERT EXERCISE 13.1) (#cbsenotes) (#ncertsolutions)

SURFACE AREAS AND VOLUMES

Class 9 Maths 

NCERT EXERCISE 13.1

CBSE Class 9 Maths - SURFACE AREAS AND VOLUMES (NCERT EXERCISE 13.1) (#cbsenotes) (#ncertsolutions)


Q1: A plastic box 1.5 m long, 1.25 m wide and 65 cm deep is to be made. It is to be open at the top. Ignoring the thickness of the plastic sheet, determine :
(i) The area of the sheet required for making the box.
(ii) The cost of sheet for it, if a sheet measuring 1 m2 costs Rs 20.

Answer: Given,
l = 1.5 m,
b = 1.25 m,
h = 65 cm = 0.65 m

(i) ∵ the box is open at the top, it has only five faces.

Surface Area (SA) for five faces = lb + 2(bh + hl)

= 1.5 × 1.25 m² + 2 (1.25 × 0.65 + 0.65 × 1.5) m²
= 1.875 + 2 (1.7875) m² = 1.875 + 3.575
= 5.45 m²

(ii) Cost of 1 m² of the sheet = ₹ 20
∴ cost of 5.45 m² of the sheet = 20 × 5.45 m² = ₹ 109 (Answer)


Q2: The length, breadth and height of a room are 5m, 4m and 3m respectively. Find the cost of white washing the walls of the room and the ceiling at the rate of Rs 7.50 per m².

Thursday 5 January 2017

Class 8/ Class 9 - Properties Of Quadrilateral Figures (Worksheet) (#CBSEClass8Maths) (#CBSEClass9Maths)

Properties Of Quadrilateral Figures

Class 8/ Class 9 - Properties Of Quadrilateral Figures (Worksheet) (#CBSEClass8Maths) (#CBSEClass9Maths)

(Worksheet)

Question. Fill in the blanks (True or False) for the properties of the following figures:


Property Parallelogram Rhombus Rectangle Square
1. Both pairs of opposite sides are parallel and equal. ? ? ? ?
2. Both pairs of opposite angles are equal. ? ? ? ?
3. Diagonals bisect each other. ? ? ? ?
4. Diagonals are equal. ? ? ? ?
5. Each angle is 90° ? ? ? ?
6. Diagonals intersect at right angles. ? ? ? ?
7. All sides are equal. ? ? ? ?


Friday 30 December 2016

CBSE Class 9 - Mathematics - CH 11 - Constructions - Very Short Questions and Answers (#CBSEClass9Notes)

Constructions

CBSE Class 9 - Mathematics - CH 11 - Constructions - Very Short Questions and Answers (#CBSEClass9Notes)

Very Short Questions and Answers
Based NCERT Class 9 Mathematics Chapter


Q1: With the help of ruler and compass, which of the following angles can be constructed?

(a) 35°
(b) 40°
(c) 37.5°
(d) 15°


Answer:  37.5° and 15° angles can be constructed using a ruler and a compass.


Q2(NCERT Exemplar): With the help of a ruler and a compass it is not possible to construct an angle of :

(A) 37.5°
(B) 40°
(C) 22.5°
(D) 67.5°