If one person is selected randomly, what is the probability that it did not pass given that it is male.

• 0.196

73. A company which produces a particular drug has two factories, A and B. 30% of the drug are made in factory A, 70% in factory B. Suppose that 95% of the drugs produced by the factory A meet specifications while only 75% of the drugs produced by the factory B meet specifications. If I buy the drug, what is the probability that it meets specifications?

• 0.81

74. Twelve items are independently sampled from a production line. If the probability any given item is defective is 0.1, the probability of at most two defectives in the sample is closest to …

• 0.8891

75. A student can solve 6 from a list of 10 problems. For an exam 8 questions are selected at random from the list. What is the probability that the student will solve exactly five problems?

• 0.133

76. Suppose that 10% of people are left handed. If 8 people are selected at random, what is the probability that exactly 2 of them are left handed?

• 0.1488

77. Suppose a computer chip manufacturer rejects 15% of the chips produced because they fail presale testing. If you test 4 chips, what is the probability that not all of the chips fail?

• 0.9995

78. Which of these has a Geometric model?

• the number of people we survey until we find someone who has taken Statistics

79. In a certain town, 50% of the households own a cellular phone, 40% own a pager, and 20% own both a cellular phone and a pager. The proportion of households that own neither a cellular phone nor a pager is

• 30%.

80. Four persons are to be selected from a group of 12 people, 7 of whom are women. What is the probability that the first and third selected are women?

• 0.3182

81. Twenty percent of the paintings in a gallery are not originals. A collector buys a painting. He has probability 0.10 of buying a fake for an original but never rejects an original as a fake, What is the (conditional) probability the painting he purchases is an original?

• 40/41

82. Suppose that the random variable T has the following probability distribution:

t | 0 1 2 --------------------------- P(T = t) | .5 .3 .2

Find .

• 0.5

83. A probability function is a rule of correspondence or equation that:

• Assigns probablities to the various values of x.

84. Which of the following is an example of a discrete random variable?

• The number of cows on a cattle ranch.

85. Which of the following is the appropriate definition for the union of two events A and B?

• The set of all basic outcomes in either A or B, or both.

86. Johnson taught a music class for 25 students under the age of ten. He randomly chose one of them. What was the probability that the student was under twelve?

• 1

87. The compact disk Jane bought had 12 songs. The first four were rock music. Tracks number 5 through 12 were ballads. She selected the random function in her CD Player. What is the probability of first listening to a ballad?

• 2/3

88. Two fair dice, one red and one blue, each have numbers 1-6. If a roll of the two dice totals 6, what is the probability that the red die is showing a 5?

• 1/5

89. A regular deck of 52 cards contains 4 different suits (Spades, Hearts, Diamonds, and Clubs) that each have 13 cards. If you randomly choose two cards from the deck, what is the probability that both cards will all be hearts?

• 1/17

90. What is the probability of drawing a diamond from a standard deck of 52 cards?

• 1/4

91. One card is randomly selected from a shuffled deck of 52 cards and then a die is rolled. Find the probability of obtaining an Ace and rolling an odd number.

• 1/26

92. The probability that a particular machine breaks down on any day is 0.2 and is independent of the breakdowns on any other day. The machine can break down only once per day. Calculate the probability that the machine breaks down two or more times in ten days.

• 0.6242

93. Let A, B and C be independent events such that P(A) = 0.5, P(B) = 0.6 and P(C) = 0.1. Calculate

• 0.73

94. The pdf of a random variable X is given by.

What are the values of µ and σ?

• 

95. What quantity is given by the formula ?

• Correlation coefficient