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Statistics & Probability

n the class intervals 10-20, 20-30, the number 20 is included in :
(A) 10-20 (B) 20-30
(C) both the intervals (D) none of these intervals

Statistics & Probability

The class marks of a frequency distribution are given as follows :
15, 20, 25, …
The class corresponding to the class mark 20 is :
(A) 12.5 – 17.5 (B) 17.5 – 22.5 (C) 18.5 – 21.5 (D) 19.5 – 20.5

Statistics & Probability

Let m be the mid-point and l be the upper class limit of a class in a continuous
frequency distribution. The lower class limit of the class is :
(A) 2m + l (B) 2m – l (C) m – l (D) m – 2l

Statistics & Probability

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

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.