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1.A truck gets involved in an accident 75% of the time if it is faulty.If it is not faulty

the probability reduces to 30% 20% of all trucks are faulty

If a truck is involved in an accident

what is the probability that it was faulty?(A)0.225 (B)0.15 (C)0.3846 (D)0.06 (E)0.24122.A nes liquid shampoo has a 75% success rate.Four customers are tested for it.What is the probability that at least three are attached to this new shampoo?(A)0.1219(B)0.3164(C)0.5781(D)0.7383(E)0.68363.Twenty-five percent of all students in a school have a 3G cellular phone.In a random sample of fifteen students

what is the probability that exactly five gave a 3G cellular phone?(A)0.8439(B)0.75(C)0.8255(D)0.25^(E)0.16514.The age of people in a city is normally distributed

which a mean of 72 years and a standard deviation of 12 years.Find two values for age that will give a symmetric area around that mean such that they include an area equal to 0.75(A)52.26

91.74(B)56.64

87.36(C)58.2

85.8(D)63.9

80.1(E)48.48

52.265.The average R