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The width of each of five continuous classes in a frequency distribution is 5 and the lower class-limit of the lowest class is 10. The upper class-limit of the highest class is: (A) 15 (B) 25 (C) 35 (D) 40

The correct answer is (C) 35 Explanation From the given data width of each five consecutive classes = 5 the lower limit of lowest class... View Article

In a frequency distribution, the mid value of a class is 10 and the width of the class is 6. The lower limit of the class is: (A) 6 (B) 7 (C) 8 (D) 12

The correct answer is (B) 7 Explanation We know that lower limit is given by Lower Limit = mid value of class – (width/2)... View Article

The range of the data: 25, 18, 20, 22, 16, 6, 17, 15, 12, 30, 32, 10, 19, 8, 11, 20 is (A) 10 (B) 15 (C) 18 (D) 26

The correct answer is (D) 26 Explanation We know that range in statistics is given by Range = Maximum value – Minimum... View Article

The class mark of the class 90-120 is: (A) 90 (B) 105 (C) 115 (D) 120

The correct answer is (B) 105 Explanation We know that Class mark = (upper limit + lower limit) / 2 From the given data upper limit=120... View Article

The water for a factory is stored in a hemispherical tank whose internal diameter is 14 m. The tank contains 50 kilolitres of water. Water is pumped into the tank to fill to its capacity. Calculate the volume of water pumped into the tank.

Given According to the given details The internal diameter of hemispherical tank = 14 m Amount of water in tank=50kl Find out We have to... View Article

A cloth having an area of 165 m² is shaped into the form of a conical tent of radius 5 m (i) How many students can sit in the tent if a student, on an average, occupies 5/7 m² on the ground? (ii) Find the volume of the cone.

Solution According to the question, Area of cloth = 165m2 The radius of conical tent = 5m Area covered by 1 student = 5/7 m2 The curved... View Article

A semi-circular sheet of metal of diameter 28cm is bent to form an open conical cup. Find the capacity of the cup.

Given According to the given details Diameter of semi-circular sheet = 28cm Find out We have to determine the capacity of the cup. Solution... View Article

A cylindrical tube opened at both the ends is made of iron sheet which is 2 cm thick. If the outer diameter is 16 cm and its length is 100 cm, find how many cubic centimeters of iron has been used in making the tube?

Given According to the given details Outer diameter d = 16cm Height = length = 100cm Thickness of iron sheet = 2cm Find out We have to... View Article

How many square metres of canvas is required for a conical tent whose height is 3.5 m and the radius of the base is 12 m?

Given According to the given details Dimensions of the conical tent are: Height = 3.5 m Radius = 12 m Find out We have to determine... View Article

Find the amount of water displaced by a solid spherical ball of diameter 4.2 cm, when it is completely immersed in water.

Given Diameter of spherical ball = 4.2 cm Find out We have to determine the amount of water displaced by a solid spherical ball when it... View Article

A storage tank is in the form of a cube. When it is full of water, the volume of water is 15.625 m³.If the present depth of water is 1.3 m, find the volume of water already used from the tank.

Given The volume of water = 15.625 m3 The present depth of the water is 1.3 m Find out We have to determine the volume of water already used... View Article

Metal spheres, each of radius 2 cm, are packed into a rectangular box of internal dimensions 16 cm × 8 cm × 8 cm. When 16 spheres are packed the box is filled with preservative liquid. Find the volume of this liquid. Give your answer to the nearest integer. [Use π = 3.14]

Given Radius of each sphere, r = 2 cm Number of spheres = 16 Dimensions of rectangular box = 16 cm × 8 cm × 8 cm Find out We... View Article

The volume of the largest right circular cone that can be fitted in a cube whose edge is 2r equals to the volume of a hemisphere of radius r. Write True or False and justify your answer in the following.

The given statement is True Explanation According to the given details Edge of the cube, l = 2r Then, the diameter of the cone = 2r... View Article

If the radius of a cylinder is doubled and its curved surface area is not changed, the height must be halved. Write True or False and justify your answer in the following.

The given statement is True Explanation Let us assume a right circular cylinder, with height as h and radius r. Then, the curved... View Article

In a right circular cone, height, radius and slant height do not always be sides of a right triangle. Write True or False and justify your answer in the following.

The given statement is True Explanation Let us assume a right circular cone, with height as h, slant height l and radius r. In a... View Article

If the radius of a right circular cone is halved and height is doubled, the volume will remain unchanged. Write True or False and justify your answer in the following.

The given statement is False Explanation Let us assume the original radius of the cone = r Let us assume the height of the cone = h. The... View Article

The volume of a sphere is equal to two-third of the volume of a cylinder whose height and diameter are equal to the diameter of the sphere. Write True or False and justify your answer in the following.

The given statement is True Explanation Let us assume the radius of the sphere = r. According to the given details height and... View Article

The total surface area of a cone whose radius is r/2 and slant height 2l is

The correct answer is (B) πr(l+(r/4)) Explanation The radius of a cone is r/2 and the slant height is 2L. Total surface area... View Article

In a cylinder, radius is doubled and height is halved, curved surface area will be (A) halved (B) doubled (C) same (D) four times

The correct answer is (C) the same Explanation Let us assume the radius of a cylinder = r unit Letus assume the height of a cylinder = h unit.... View Article

A cone is 8.4 cm high and the radius of its base is 2.1 cm. It is melted and recast into a sphere. The radius of the sphere is: (A) 4.2 cm (B) 2.1 cm (C) 2.4 cm (D) 1.6 cm

The correct answer is (B) 2.1 cm Explanation Height of cone, h = 8.4cm Radius of base, r = 2.1cm Thus volume of a cone = × π... View Article