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Statistics and Probability

For the following distribution :

Marks                Number  of  students

Below 10           3

Below 20          12

Below 30          27

Below 40          57

Below 50          75

Below 60          80

the modal class is

(A) 10-20 (B) 20-30 (C) 30-40 (D) 50-60

Statistics and Probability

Consider the following frequency distribution :

The upper limit of the median class is

(A) 17 (B) 17.5 (C) 18 (D) 18.5

Statistics and Probability

For the following distribution :

the sum of lower limits of the median class and modal class is

(A) 15 (B) 25 (C) 30 (D) 35

Statistics and Probability

The abscissa of the point of intersection of the less than type and of the more than type cumulative frequency curves of a grouped data gives its

(A) mean (B) median     (C) mode (D) all the three above 

Statistics and Probability

While computing mean of grouped data, we assume that the frequencies are

(A) evenly distributed over all the classes

(B) centred at the classmarks of the classes

(C) centred at the upper limits of the classes

(D) centred at the lower limits of the classes

Statistics and Probability

A bag contains 3 red balls, 5 white balls and 7 black balls. What is the probability that a ball drawn from the bag at random will be neither red nor black?

(A) 1/5 (B)1/3 (C)7/15 (D) 8/15

Statistics and Probability

A card is selected at random from a well shuffled deck of 52 playing cards. The probability of its being a face card is

(A) 3/13 (B)4/13 (C)6/13 (D)9/13

Statistics and Probability

Which of the the following can be the probability of an event?

(A) – 0.04 (B) 1.004 (C) 18/23 (D)8/7

Statistics and Probability

Consider the following frequency distribution of the heights of 60 students of a class :

Height  (in  cm)          Number  of  students

150-155                             15

155-160                             13

160-165                             10

165-170                             8

170-175                             9

175-180                             5

The sum of the lower limit of the modal class and upper limit of the median class is

(A) 310 (B) 315 (C) 320 (D) 330

Statistics and Probability

In the following distribution :

Monthly  income  range  (in  Rs)         Number of families

Income more than Rs 10000               100

Income more than Rs 13000               85

Income more than Rs 16000               69

Income more than Rs 19000               50

Income more than Rs 22000               33

Income more than Rs 25000               15

the number of families having income range (in Rs) 16000 – 19000 is

(A) 15 (B) 16 (C) 17 (D) 19