Chapter 14 Statistics Ex 14.1
Chapter 14 Statistics Ex 14.1 Question 1. A survey was conducted by a group of students as a part of their environment awareness programme, in which they collected the following data regarding the number of plants in 20 houses in a locality. Find the mean number of plants per house. Which method did you use […]
Chapter 13 Surface Areas and Volumes Ex 13.4
Chapter 13 Surface Areas and Volumes Ex 13.4 Unless stated otherwise, take π = 22/7 Question 1. A drinking glass is in the shape of a frustum of a cone of height 14 cm. The diameters of its two circular .ends are 4 cm and 2 cm. Find the capacity of the glass. Solution: Question 2. […]
Chapter 13 Surface Areas and Volumes Ex 13.3
Chapter 13 Surface Areas and Volumes Ex 13.3 Unless stated otherwise, take π = 227 Question 1. A metallic sphere of radius 4.2 cm is melted and recast into the shape of a cylinder of radius 6 cm. Find the height of the cylinder. Solution: Given: radius of metallic sphere = 4.2 cm ∴ Volume = 4/3π(4.2)³ […]
Chapter 13 Surface Areas and Volumes Ex 13.2
Chapter 13 Surface Areas and Volumes Ex 13.2 Unless stated otherwise, take π = 22/7 Question 1. A solid is in the shape of a cone standing on a hemisphere with both their radii being equal to 1 cm and the height of the cone is equal to its radius. Find the volume of the […]
Chapter 13 Surface Areas and Volumes Ex 13.1
Chapter 13 Surface Areas and Volumes Ex 13.1 Question 1. 2 cubes each of volume 64 cm3 are joined end to end. Find the surface area of the resulting cuboid. Solution: Volume of one cube = 64 cm3 Let edge of one cube = a Volume of the cube = (edge)3 a3 = 64 ⇒ a = […]
Chapter 12 Areas Related to Circles Ex 12.3
Chapter 12 Areas Related to Circles Ex 12.3 Question 1. Find the area of the shaded region in the given figure, if PQ = 24cm, PR = 7cm and O is the centre of the circle. Solution: Question 2. Find the area of the shaded region in the given figure, if radii of the two […]
Chapter 12 Areas Related to Circles Ex 12.2
Chapter 12 Areas Related to Circles Ex 12.2 Question 1. Find the area of a sector of a circle with radius 6 cm if angle of the sector is 60°. Solution: Radius of the sector (r) = 6 cm Central angle of the sector = 60° Question 2. Find the area of a quadrant of […]
Chapter 12 Areas Related to Circles Ex 12.1
Chapter 12 Areas Related to Circles Ex 12.1 Question 1. The radii of two circles are 19 cm and 9 cm respectively. Find the radius of the circle which has circumference equal to the sum of the circumferences of the two circles. Solution:Given: radius of 1st circle (R1) = 19 cm ∴ Circumference of 1st circle = 2πR1 = […]
Chapter 11 Constructions Ex 11.2
Chapter 11 Constructions Ex 11.2 In each of the following, give the justification of the construction also: Question 1. Draw a circle of radius 6 cm. From a point 10 cm away from its centre, construct the pair of tangents to the circle and measure their lengths. Solution: Steps of Construction: 1. Draw a circle […]
Chapter 11 Constructions Ex 11.1
Chapter 11 Constructions Ex 11.1 In each of the following, give the justification of the construction also: Question 1. Draw a line segment of length 7.6 cm and divide it in the ratio 5:8. Measure the two parts. Solution: Steps of Construction: 1. Draw a line segment AB = 7.6 cm. 2. Draw an acute […]