Question

The means of the number of revolutions per minute of two competing engines are to be compared. Thirty engines are randomly assigned to be tested. Both

Significance tests
ANSWERED
asked 2021-05-25
The means of the number of revolutions per minute of two competing engines are to be compared. Thirty engines are randomly assigned to be tested. Both populations have normal distributions. Table 10.9 shows the result. Do the data indicate that Engine 2 has higher RPM than Engine 1? Test at a 5% level of significance. EngineSample Mean Number of RPMPopulation Standard Deviation 11,50050 21,60060 Table 10.9

Answers (1)

2021-05-26
We can conclude that we reject the null hypothesis. These is sufficient evidence to conclude that Engine 2 runs at a higher RPM than Engine 1.
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