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Write the sum using summation notation, assuming the suggested pattern continues. 2 – 6 + 18 – 54 + … (7 points)

(04.01 MC)  To increase sales, a cell phone store began giving a free month of service on some cell plan purchases. Customers were unaware whether they would receive the free month until after purchase. The store manager claimed that one in eight customers received the free month. Nine customers each buy a cell phone plan. Let X = the number of customers that receive a free month of cell phone service.Part A: Is X a binomial random variable? Explain. (3 points)Part B: What is the mean and standard deviation of X? Provide an interpretation for each value in context. (4 points)Part C: Three of the nine customers receive a free month of service. Is the store’s claim accurate? Compute P(X ≥ 3) and use the result to justify your answer. (3 points) (10 points)

Find the first six terms of the sequence. a1 = -1, an = 2 • an-1 (7 points)  

(01.02, 02.01, 06.02 MC) Scott is the owner of a tool and die shop. He has hired you to check his machine’s calibration prior to starting production on a large order. To check this, you set the machine to create 1.5 inch screws and manufacture a random sample of 200 screws. That sample of screws has an average length of 1.476 inches with a standard deviation of 0.203 inches.Does this sample provide convincing evidence that the machine is working properly or should it be shut down for repairs?

(05.05 MC)  The number of minutes of commercials shown per hour was determined 12 times at random. The results are 14, 13, 15, 11, 17, 18, 11, 14, 17, 18, 15, and 13 minutes of commercials shown per hour. Construct a 98% confidence interval for the mean number of minutes of commercials shown per hour. (4 points)

Find the center, vertices, and foci of the ellipse with equation 3×2 + 8y2 = 24. (5 points)

Find the sum of the arithmetic sequence. 15, 17, 19, 21, …, 33 (7 points)

At what age would you be worried if a child is not able to sit without support:

Determine the interval on which the function in the graph below is decreasing. ​

Write the sum using summation notation, assuming the suggested pattern continues. 2 – 8 + 32 – 128 + … (5 points)