Assume, as stated in the problem, that service times are exponentially distributed with a mean of one minute. Suppose you’ve been watching a man on one of the phones, and he’s been talking for 30 seconds so far. On average, how much longer will he remain on the phone before hanging up? 30 seconds 45 seconds 60 seconds 90 seconds the information given does not allow us to answer the question. If = 30, = 5, and k = 3, then (/)k/k! =   a) 0 b) 1/6 c) 6 d) 6 e) 36 Problems 22-24 deal with the following situation. A normal six sided die has the following property: opposite faces on the die always add to seven. Thus, the face is always opposite the face, the face is always opposite the face, and the face is “1” “6” “2” “5” “3” always opposite the face. “4” 22. Suppose we roll a normal six sided die, then add the numbers on its top face and its bottom face. This total will always be seven. have an expected value of seven. have a median value of seven. all of the above (a-c) are true. none of the above (a-c) are necessarily true. Suppose we take the number of the top of our normal six die, and it by the number on the multiply bottom. The expected value of the top is 3.5. The expected value of the bottom is 3.5. But the expected value of is not 3.5 3.5 = 12.25. The reason we cannot rely on this the top times the bottom calculation is that the top and the bottom value are independent. the top and the bottom are different. the top and the bottom value are dependent. the top and the bottom values are symmetric; that is, we could interchange top and bottom without changing the result. the product of the top and bottom of the die cannot be a fractional value. Roll one normal six sided die. We let P = T B, where T is the number rolled on the top of the die, and B is the number on the bottom of the die. Then E(T B) is closest to a) 8 c) 9 d) 10 e) 12
Assume, as stated in the problem, that service times are exponentially distributed with a mean of one minute. Suppose you’ve been watching a man on one of the phones, and he’s been talking for 30 seconds so far. On average, how much longer will he remain on the phone before hanging up? 30 seconds 45 seconds 60 seconds 90 seconds the information given does not allow us to answer the question. If  = 30,  = 5, and k = 3, then (/)k/k! = a) 0 b) 1/6 c) 6 d) 6 e) 36 Problems 22-24 deal with the following situation. A normal six sided die has the following property: opposite faces on the die always add to seven. Thus, the “1” face is always opposite the “6” face, the “2” face is always opposite the “5” face, and the “3” face is always opposite the “4” face. 22. Suppose we roll a normal six sided die, then add the numbers on its top face and its bottom face. This total will always be seven. have an expected value of seven. have a median value of seven. all of the above (a-c) are true. none of the above (a-c) are necessarily true. Suppose we take the number of the top of our normal six die, and multiply it by the number on the bottom. The expected value of the top is 3.5. The expected value of the bottom is 3.5. But the expected value of the top times the bottom is not 3.5 3.5 = 12.25. The reason we cannot rely on this calculation is that the top and the bottom value are independent. the top and the bottom are different. the top and the bottom value are dependent. the top and the bottom values are symmetric; that is, we could interchange top and bottom without changing the result. the product of the top and bottom of the die cannot be a fractional value. Roll one normal six sided die. We let P = T B, where T is the number rolled on the top of the die, and B is the number on the bottom of the die. Then E(T B) is closest to a) 8 c) 9 d) 10 e) 12
Sample%20Exam%203,%20Test%20B.docx