Probability and Statistics Mid - II, November - 2014

1.If the maximum error with probability0 .95 is 1.2.Standard deviation of the population is 10. Then sample size is......
  • 267
  • 129
  • 225
  • 169
Answer: A
2.A random sample of size 90 was taken whose S.D is 26, then the maximum error with 95% confidence is
  • 3.781
  • 2.98
  • 6.981
  • 5.372
Answer: D
3.If expected frequencies Ei and (Oi − Ei )2 are given by 
(0i - Ei)2 324 729 82
Ei 30 36 34
Then x2 = 
  • 14.5
  • 25.6
  • 33.4
  • 30.2
Answer: C
4.The letters arrive at a typist per 15 minutes and the typist takes 15 minutes to type the letters. If the typing cost is 2 Rs per hour the average idle time cost of the type writer per day is
  • Rs. 8
  • Rs.5
  • Rs. 4.50
  • Rs.10
Answer: A
5.The probability that 1 Unit served in the time interval is
Answer: B
6.If the probability transition ,matrix is  and the initial probabilities are P1(0) = 0.4, P2 (0) = 0.3, P3 (0) = 0.3 then P1(1) =
  • 0.27
  • 0.29
  • 0.31
  • 0.33
Answer: B
7.No quene forms if the traffic intensity is
  • < 1
  • > 1
  • 1
  • infinity
Answer: A
8.The standard deviations of two samples of sizes 50 and 75 are 4 and 5 respectively, then the Maximum error with 99% confidence is
  • 2.3843
  • 2.9643
  • 2.9231
  • 2.0854
Answer: D
9.Variance of queue length is
Answer: C
10.If all states communicate, then the state is _______
  • recurrent
  • irreducible
  • steady
  • transient
Answer: B
11.If the standard deviation is 18and n = 300,then the Maximum error with 95% confidence is………………………..
Answer: 2.0369
12.If the maximum error with probability 0.95 = 0.5 Standard deviation of the population is 1.6. Then sample size is............................
Answer: 40
13.If the mean breaking of copper wire is 505 lbs with a standard deviation of 15 lbs. The size of the sample is 49 Maximum error with 0.95 probability is………………….
Answer: 4.2
14.In a random sample of 100 packages shipped by air freight 13 had some damage.The standard error of proportions is ......................
Answer: 0.0336
15.500 eggs are taken from a large consignment and 50 are found to be bad. the Maximum error of proportions with 95% confidence is………………………..
Answer: 0.026
16.Expected queue length is ……………………….
Answer:
17.The differential equation of the probability that there is 0 Unit arrives in time t is…………………….
Answer:
18.The time taken by a radio repairman to repair is 20 minutes .15 arrive per 8 hours day. The idle time of the repair man is……………………
Answer: 3 hours
19.Three boys are playing a game. One throws the ball to others with equal probabilities the transition probability matrix is …………………….
Answer:
20.A state forming a closed set by itself is called ………………………….. state
Answer: A n absorbing