M.C.A. (Science) (Semester III) (CBSC) Examination, 2017
COMPUTER ORIENTED STATISTICS
Day Date: Thursday, 27-04-2017 Max. Marks: 70
Time: 02.30 PM to 05.00 PM
Instructions Question No.1 and 2 are compulsory.
Attempt any 3 questions from Q.NO. 3 to Q. No. 7
Figures to the right indicate full marks.
Use of simple or scientific calculator is allowed.
Q.1 Select most correct alternative: 10
For a frequency distribution if A.M. mode, then it is
symmetric +vely skewed
vely skewed None of these

305 2.5 160 None of
these
If each observation is multiplied by 10, then rang becomes
as it is increased by 10
10 times none of these
If P then events A and B are
exhaustive certain
mutually exclusive equally likely
If event A is subset of event then P
1 Zero
If X →H then possible values taken by X are
3 2,…., 8
2,…., 20 None of these
If abd be the p.m.f and c.d.f of a discrete r.v. then

P(X P(X
F(X None of these
Statistical table are used to obtain probabilities of events related
to distribution only.
exponential normal
both and none of these
Page 1 of 3
Both regression coefficients have same algebraic sign if
correlation is
perfect high degree low degree all of these
10) Frequency is
A positive integer always
A number showing how many times a particular item
repeated in the data
Both and
None of these
State whether following statements are True or False: 04
Measures of dispersion provides a single value that represents
the whole data
Intersection of mutually exclusive events is a null event.
Regression coefficient gives rate of change in dependent
variable per unit change in dependent variable.
Multiplicative congruential generator is one of the methods of
generating random numbers deterministically.
Q.2 Define mutually exclusive events, if A and B are mutually
exclusive events with
0.35 and 0.42, find PAUB
04
ii) Given: 50, 354. Find coefficient of variation. 04
Define Geometric distribution and state its additive property. 03
ii) Find value of K if A.M. of observations 20, 15, 12, 10 is 14. 03
Q.3 The probability that a new product will be successful if a competitor
dose not launches a similar product is 0.67. The probability that a
new product will be successful in the presence of competitor's new
product is 0.42. The probability that the competitor will launch a
new product is 0.35. What is probability that the product will be
success?
07
The p.m.f. of discrete r.v. X is
k x2,
Find value of k ii) x 1 iii) x2 10)
07
Q.4 Define exponential distribution. If life time of certain type of bulb
follows exponential distribution with mean life time 1200 hours.
Find number of bulbs out of 1000 those are survived more than
1500 hours.
07
Give procedure of generating random observations from uniform
distribution over
07
Q.5 A random variable X has hyper geometric distribution with
parameters
07
Define tabulation, explain different parts of good table. 07
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Q.6 Define c.d.f of discrete r.v. State its properties. 07
The following is the distribution of height of students find medium. 07
Height
(in cm.) 140-145 145-150 150-155 155-160 160-165 165-170
No. of
student 10 18 22 20 14 9
Q.7 A sample of 20 pairs of observations on gives the following
information.
Σx 320, ΣY 210, ΣX2 3200, ΣY2 2100, ΣXY 1945
Obtain the equation of line of regression X on Y and hence
estimate X for Y 20.
07
Define binomial distribution. If a computer centre has 10
computers. The chance of their failure is same during the given
period and is equal to 0.3. find probability that during a given period
at least 2 computers will fail.