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A small business ships specialty homemade candies to anywhere in the world.  Past records indicate that the weight of orders is normally distributed.  Suppose a random sample of 16 orders is selected and each is weighed.  The sample mean was found to be 110 grams with a standard deviation of 14 grams.  Which of the following statements is true?

A company manufacturing computer chips finds that 8% of all chips manufactured are defective. To decrease the percentage of defective chips, management decides to provide additional training to those employees hired within the last year.  After training was implemented, a sample of 450 chips revealed only 27 defects.  A hypothesis test is performed to determine if the additional training was effective in lowering the defect rate.  Which of the following statement is true about this hypothesis test?

An army depot that overhauls ground mobile radar systems is interested in improving its processes.  One problem involves troubleshooting a particular component that has a high failure rate after it has been repaired and reinstalled in the system.  The shop floor supervisor believes that having standard work procedures in place will reduce the time required for troubleshooting this component.  Time (in minutes) required troubleshooting this component without and with the standard work procedure is recorded for a sample of 19 employees. Assuming that we define our differences as Time without standard work procedure – Time with standard work procedure, the correct alternative hypothesis is ________________________ .

A manufacturer of cheese filled ravioli supplies a pizza restaurant chain.  Based on data collected from its automatic filling process, the amount of cheese inserted into the ravioli is normally distributed.  To make sure that the automatic filling process is on target, quality control inspectors take a sample of 25 ravioli.  The correct value of t* to construct a 98% confidence interval for the true mean amount of cheese filling is ________________________ .

An army depot that overhauls ground mobile radar systems is interested in improving its processes.  One problem involves troubleshooting a particular component that has a high failure rate after it has been repaired and reinstalled in the system.  The shop floor supervisor believes that having standard work procedures in place will reduce the time required for troubleshooting this component.  Time (in minutes) required troubleshooting this component without and with the standard work procedure is recorded for a sample of 19 employees. The standard error of the mean difference is ________________________ . Without Standard Work Procedure With Standard Work Procedure DifferenceWithout – With 142 119 23 144 118 26 153 126 27 148 119 29 146 121 25 149 125 24 138 116 22 145 120 25 153 124 29 160 138 22 163 135 28 170 144 26 169 142 27 151 128 23 152 131 21 167 141 26 164 140 24 165 140 25 163 138 25

In a metal fabrication process, metal rods are produced to a specified target length of 15 feet.  Suppose that the lengths are normally distributed.  A quality control specialist collects a random sample of 16 rods and finds the sample mean length to be 14.8 feet and a standard deviation of 0.65 feet.  The 95% confidence interval for the true mean length of rods produced by this process is ________________________ .

A pharmaceutical company wants to answer the question whether it takes longer than 45 seconds for a drug in pill form to dissolve in the gastric juices of the stomach. A sample was taken from patients taking the given drug in pill form and times for the pills to be dissolved were measured. State assumptions of the test. 

Molly’s Reach, a regional restaurant and gift shop, has recently launched an increased sales campaign, particularly focused on their gift shop. To determine if their proposal is of interest, they plan to survey a random sample of their regular customers. One member of the management team at Molly’s Reach suggests that their survey could be conducted online.  Customers logging on to the online store would be asked to take a few minutes to complete the survey and would be offered a coupon as incentive to participate.  Which of the following statements is true?

Molly’s Reach, a regional restaurant and gift shop, has recently launched an increased sales campaign, particularly focused on their gift shop. To determine if their proposal is of interest, they plan to survey a random sample of their regular customers. All regular Molly’s Reach customers is known as the ________ of the study.

Based on data collected from its production processes, Crosstiles Inc. determines that the breaking strength of its most popular porcelain tile is normally distributed with a mean of 400 pounds per square inch and a standard deviation of 12.5 pounds per square inch.  Based on the 68-95-99.7 Rule, about what percent of its popular porcelain tile will have breaking strengths between 375 and 425 pounds per square inch?