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Statistics & Probability

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

Statistics & Probability

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

Statistics & Probability

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

Statistics & Probability

The class-mark of the class 130-150 is :
(A) 130 (B) 135 (C) 140 (D) 145

Statistics & Probability

The marks obtained by 17 students in a mathematics test (out of 100) are given below :
91, 82, 100, 100, 96, 65, 82, 76, 79, 90, 46, 64, 72, 68, 66, 48, 49.
The range of the data is :
(A) 46 (B) 54 (C) 90 (D) 100

Surface Area & Volumes

30 circular plates, each of radius 14 cm and thickness 3cm are placed one above the another to form a cylindrical solid. Find :
(i) the total surface area
(ii) volume of the cylinder so formed.

Surface Area & Volumes

A sphere and a right circular cylinder of the same radius have equal volumes. By what percentage does the diameter of the cylinder exceed its height ?

Surface Area & Volumes

A cube of side 4 cm contains a sphere touching its sides. Find the volume of the gap in between.

Surface Area & Volumes

The volumes of the two spheres are in the ratio 64 : 27. Find the ratio of their surface areas.

Surface Area & Volumes

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.