8) A local tennis pro-shop strings tennis rackets at the tension (pounds per square inch) requested by 8 ) the customer. Recently a customer made a claim that the pro-shop consistently strings rackets at lower tensions, on average, than requested. To support this claim, the customer asked the pro shop to string 6 new rackets at 42 psi. Suppose the two-tailed P-value for the test described above (obtained from a computer printout) is 0.07. Give the proper conclusion for the test. Use a = 0.05. A) Accept Ho and conclude that u, the true mean tension of the rackets, equals 42 psi. B) Reject Ho and conclude that u, the true mean tension of the rackets, equals 42 psi. C) There is insufficient evidence to conclude that u, the true mean tension of the rackets, is less than 42 psi. D) There is sufficient evidence to conclude that u, the true mean tension of the rackets, is less than 42 psi. 9) Smith is a weld inspector at a shipyard. He knows from keeping track of good and substandard 9) welds that for the afternoon shift 5% of all welds done will be substandard. If Smith checks 300 of the 7500 welds completed that shift, what is the probability that he will find more than 25 substandard welds? A) 0.4960 B) 0.9960 C) 0.5040 D) 0.0040 10) Many people think that a national lobby's successful fight against gun control legislation is 10) reflecting the will of a minority of Americans. A random sample of 4000 citizens yielded 2250 who are in favor of gun control legislation. Estimate the true proportion of all Americans who are in favor of gun control legislation using a 90% confidence interval. Express the answer in the form p + E and round to the nearest ten-thousandth. A) 0.4375 + 0.4048 B) 0.5625 = 0.0129 C) 0.4375 + 0.0129 D) 0.5625 + 0.4048 11) In a carnival game, a person wagers $2 on the roll of two dice. If the total of the two dice is 2, 3, 4, 11) 5, or 6 then the person gets $4 (the $2 wager and $2 winnings). If the total of the two dice is 8, 9, 10, 11, or 12 then the person gets nothing (loses $2). If the total of the two dice is 7, the person gets $0.75 back (loses $0.25). What is the expected value of playing the game once? A) -$0.42 B) -$0.04 C) $0.00 D) $2.00 12) If a population proportion is believed to be 0.6, how many items must be sampled to ensure that 12) the sampling distribution of p will be approximately normal? Assume that the size of the population is N = 10,000. A) 13 B) 60 C) 42 D) 30 13) The contingency table below shows the results of a random sample of 200 registered voters that 13) was conducted to see whether their opinions on a bill are related to their party affiliation. Use a = 0.05. Party Opinion Approve Disapprove No Opinion Republican 42 20 14 Democrat 50 24 18 D) 26206.00 m Independent 10 16 6 Find the critical value x , to test the claim of independence. andfro and a standard deviation A) 11.143 B) 13.277 C) 9.488 D) 7.779
