Reference no: EM132330119
Questions -
Q1. The management of White Industries is considering a new method of assembling its golf cart. The present method requires 42.3 minutes, on the average, to assemble a cart. The mean assemble time for a random sample of 24 carts, using the new methods, was 40.6 minutes, and the standard deviation of the sample was 2.8 minutes. Using the .10 level of significance, can we conclude that the assembly time using the new method is faster?
Q2. The management of Discount Furniture, a chain of discount furniture stores in Northeast, designed an incentive plan for salespeople. To evaluate this innovative plan, 12 salespeople were selected at random, and their weekly incomes before and after the plan were recorded.
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Before
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After
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Sid M.
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$320
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$340
|
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Carol Q.
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$290
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$285
|
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Tom J.
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$421
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$475
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Andy J.
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$510
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$510
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|
Jean S.
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$220
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$230
|
|
Jack W.
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$402
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$500
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Peg M.
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$625
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$631
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Anita L.
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$560
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$560
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John C.
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$360
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$365
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|
Carl U.
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$431
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$431
|
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A.S. K.
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$506
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$525
|
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Fern L.
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$515
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$639
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Was there a significant increase in the typical salesperson's weekly income due to the innovative incentive plan? Use the .05 significance level. Estimate the p-value, and interpret it.
Q3. Fairfield Homes is developing two parcels near Pigeon Fork, Tennessee. In order to test different advertising approaches, they use different media to reach potential buyers. The mean annual family income for 75 people making inquiries at the first development is $150,000 with a standard deviation of $40,000. A corresponding sample of 120 people at the second development had a mean of $ 180,000, with a standard deviation of $30,000. At the .05 signification level, can Fairfield conclude that the population means are different?
Q4. a. As a probability event, you flip 4 fair coins (each one has a 50-50 chance of landing on heads), find the probability distribution for the probabilities of getting 0 heads, 1 head, 2 heads, 3 heads, OR 4 heads on the four coins.
b. Instead of having four "fair" coins, you flip four coins where the probability of getting heads is 55% and tails is 45%; find the probability distribution for the probabilities of getting 0 heads, 1 head, 2 heads, 3 heads, OR 4 heads on the four coins.