Test Bank Zone Statistics

Principle’s statistic Test Bank – Final Principle’s statistic Test Bank – Final -Exam 1) If the grades of students in Principles of statistics are distributed through the N(60, 100 then the percentage of students with grades between 65 and 70 = 1- 14.98% 2- 69.15% 3- 52.34% 4- 84.13% 2) it will know that the proportion of smokers in Jordan = 0.7, using a random sample of size n = 10 Jordanian persons. the standard deviation of the estimated proportion of smokers in this sample 1- 0.1449 1 2- 0.2 3- 0.30 4- 0.70 3) Suppose that the variance of the sample mean is equals 25 and the sample size is 6,then the population variance is 1- 30 2- 150 3- 43.30 4- 25 Principle’s statistic Test Bank – Final 4) If the discrete random variable X takes on the values 1, 2, 3 and if P(X = 1) = P(X = 3) =0.2, then the mean of X = 1- 1.4 2- 2 3- 1.8 4- 0.6 5) If the random variable X is distributed through the N(20, 25),then P(X> 30) = 1- 0.0228 2- 0.9772 3- 0.8431 4- 0.9614 6) Ali went to play a lucky game. If 135 tickets of this lucky game were sold and the probability of Ali winning is (1/9), then the number of tickets bought by Ali is equal to 1-15 2-10 3-20 4-5 Principle’s statistic Test Bank – Final 7) If the random variable X is distributed through the Normal distribution with mean = p and unknown variance. At the significance level a = 10%, to test H0: u = 60 vs H1: p< 60, using a random sample of size n = 16 with sample mean 65 and sample variance 400, the value of the test statistic = 1- 1.282 2- 1 3- -1.282 4- -1 8) The statistical measure for which 25% of the observations are greater than it is called 1- the first quartile 2- the interquartile range 3- the third quartile 4- the mode 9) If the mean of 3 observations = 5, and the variance 25. If we add a new observation which is equal 1 to the 3 observations, then the variance of the 4 observations is equal to 1- 4 2- 40.8666 3- 122.3333 4- 20.6666 Principle’s statistic Test Bank – Final 10) Given that the random variable X is distributed according to the binomial distribution Bin( n, 0.4) , if the variance of X = 1.2 , then P(X = 3)= 1- 0.2304 2- 0.48 3- 2 4- 0.6 11) Suppose that the probability of getting a job for a person is (x / 3). If the probability of not getting the job is (2 / 3) then the value of x is equal to 1- 1.5 2- 3 3- 2 4- 1 12) An examination consists of two papers, Paper 1 and Paper 2. The probability of failing in Paper 1 is 0.3 and that in Paper 2 is 0.2. Given that a student has failed in Paper 2, the probability of failing in Paper 1 is 0.6. The probability of a student failing in both the papers is equal to 1- 0.06 2- 0.12 3- 0.18 4- 0.5 Principle’s statistic Test Bank – Final 13) If the weights of children are distributed according to the N(40, 125), then the probability that the total weight of any 5 children will be less than or equal to 210 kg = 1- 0.6179 2- 0.6554 3- 0.6915 4- 0.7881 14) Suppose that for a random sample, the mean is 4 and the coefficient of variation is 87.5% then the value of the standard deviation is equal to 1- 4.5 2- 3.5 3- 3 4- 2.5 Principle’s statistic Test Bank – Final 15) If the random variable X distributed according to the normal distribution with known variance W, By using a random sample of size n= 25, if the interval (54,66) is a 95% confidence interval for the population mean, then W = 1- 234.27738 2- 1.96 3- 15.306122 4- 1.645