Question

a) An engineer wishes to compare the mean lifetimes of two types of transistors in an application involving high-temperature performance. A random sample of 30 transistors of type A and a random sample of 30 oftype B were tested and the lifetime (minutes) of each transistor recorded. Appropriate plots and Minitab output are given below. Write a short report on whether there is evidence of a significant difference in the mean lifetime between the two transistor types [20 marks Descriptive Statistics: Type A, Type B Variable Minimum Maximum Mean StDev Q1 Median Q3 Туре А Туре в 30 1777.4 1576.4 1351.0 2071.3 158.7 1659.2 1779.4 1896.9 1465.0 1592.9 1746.5 30 203.0 1138.2 1873.2 Boxplot of Transistor Lifetimes by Type 2200 2000 1800 1600 3400 1200 1000- Type A Type B Two-Sample T-Test and CI: Type A, Type B Two-sample T for Type A vs Type B SE StDev Mean Mean 29 Туре А Туре в 30 1777 159 203 37 30 1576 Difference-u (Type A)- (Type B) Estimate for difference: 95 CI for difference: T-Test of difference 0 (vs 201.0 (106.7, 295.3) DF 54 P-Value T-Value-4.27 0.000 (sanou uan

Answer 1

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