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Ten measurements of impact energy on specimens of A238 steel at 60 ºC are as follows:...

Ten measurements of impact energy on specimens of A238 steel at 60 ºC are as follows: 64.1, 64.7, 64.5, 64.6, 64.5, 64.3, 64.6, 64.8, 64.2, and 64.3 J.

a. Use the Student’s t distribution to find a 95% confidence interval for the impact energy of A238 steel at 60 ºC.

b. Use the Student’s t distribution to find a 98% confidence interval for the impact energy of A238 steel at 60 ºC.

Solutions

Expert Solution

Using TI-83 plus calculator we get, the following confidence interval for population mean,

a) The 95% confidence interval for the impact energy of A238 steel at 60 ºC is, (64.298, 64.622)

b) The 98% confidence interval for the impact energy of A238 steel at 60 ºC is, (64.257, 64.663)


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