Download JNTUH (Jawaharlal nehru technological university) MCA (Master of Computer Applications) 1st Sem (First Semester) Regulation-R09 2020 January F3104 Probability And Statistics Previous Question Paper
R09
Code No: F3104
JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD
MCA I Semester Examinations, January - 2020
PROBABILITY AND STATISTICS
Time: 3hrs
Max.Marks:60
Answer any five questions
All questions carry equal marks
- - -
S 1.a) There are 25 cards numbered 1 to 25. Two cards are drawn. Find the probability that
their sums is i) even
ii) a multiple of 3.
b)
There are three boxes. I contains- 10 light bulbs out of which 4 are defective II,
contains- 6 light bulbs out of which 1 is defective, III contains- 8 light bulbs out of
which 3 are defective. A box is chosen at random and a bulb is selected. If it is
defective then find the probability that it is from:
i) Box- I
ii) Box-II
iii) Box-III.
[6+6]
2.a)
A random variable X has the following distribution
x
1 2 3 4
5
P(X = x) 1
1 1 1 1
2
4
8
16
16
Find: i) The mean
ii) variance.
iii) P(1< X< 4)
b)
The probability of man hitting a target is 1/3. If he fires 6 times, find the probability of
hitting: i) At the most 5 times ii) At least 5 times iii) Exactly once.
[6+6]
3.a)
Average number of accidents on any day on a national highway is 1.6. Determine the
probability that the number of accidents is i) at least one ii) at the most one
b)
The marks obtained by 1000 students is normally distributed with mean 78 % and
Standard deviation 11%. Determine
i) How many get more than 90%.
ii) How many students get between 75% and 90%.
[6+6]
4.
A population consists of five numbers 5,10,15,20 .Consider all Samples of size two
which can be taken with replacement from this population. Find:
a) The population mean.
b) The population Standard deviation.
c) The mean of the sampling distribution of means.
d) Standard deviation of the sampling distribution of means.
[12]
5.a)
A Random sample of 100 items is taken from a population whose standard deviation
is 5.1 The mean of the sample is 21.6. Construct 95% confidence interval for the mean.
b)
A sample of 121 students is found to have a mean weight of 68 kgs. Can this be
regarded as a sample from a population with mean weight 75 kgs and standard
deviation 31 kgs?
[6+6]
6.a)
A simple sample of heights of 6400 Englishmen has a mean of 67.85 and Standard
deviation of 2.56 inches. While a simple sample of heights of 1600 Australian has a
mean of 68.55 and a S.D. of 2.52 inches Test the significance between the two mean.
b) 400 articles from a factory are examined and 3% are found to be defective. 600 similar
articles from a second factory are found to be 2 % defective. Test the significance
between the differences of two proportions at 5% level.
[6+6]
7.
Two random sample are drawn from two normal populations are as follows.
S
Sample I 17
27 18 25 27 29 13 17
Sample II 16
16 20 27 26 25 21
Test whether two populations have been drawn from the same normal population. [12]
8.
The marks obtained by 10 students in Mathematics and Statistics are given below. Find
the Coefficient of correlation between the two subjects and the regression lines. [12]
Marks in Maths
75
30
60
80
53
35
15
40
38
48
Marks in Statistics
85
45 54
91
38
63
35
43
45
44
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This post was last modified on 16 March 2023