The life in hours of a battery is known to be approximately normally distributed, with standard deviation σ=1.25 hours. a random sample of 10 batteries has a mean life of x¯=40.5 hours. (a) is there evidence to support the claim that battery life exceeds 40 hours? use α=0.050. (b) what is the p-value for the test in part () what is the β-error for the test in part (a) if the true mean life is 42 hours? (d) what sample size would be required to ensure that β does not exceed 0.1 if the true mean life is 44 hours? (e) round your answers to three significant digits.

At a sale this week, a desk is being sold for $213. this is a 29% discount from the original price. what is the original price?

Identify the slope an intercept of the following linear equation y = 1/5x - 6 a. slope: 1/5; intercept: -6 b. slope: 5; intercept: -6 c. slope: -1/5; intercept: 6 d. slope: 1/5; intercept: 6

Acell phone company offers two plans to its subscribers. at the time new subscribers sign up, they are asked to provide some demographic information. the mean yearly income for a sample of 40 subscribers to plan a is $45,000 with a standard deviation of $9,200. for a sample of 25 subscribers to plan b, the mean income is $64,300 with a standard deviation of $7,100. at the 0.025 significance level, is it reasonable to conclude the mean income of those selecting plan b is larger? assume unequal population standard deviations. hint: for the calculations, assume the plan a as the first sample. what is the decision rule? (negative amount should be indicated by a minus sign. round your answer to 3 decimal places.) compute the value of the test statistic. (negative amount should be indicated by a minus sign. round your answer to 2 decimal places.) what is your decision regarding h0 ? reject h0 fail to reject h0 compute the p-value. less than 0.01 between 0.01 and 0.025 between 0.025 and 0.05 between 0.05 and 0.10 greater than 0.10