1. The mean life span of population of light bulbs manufactured by a particular company is...

1. The mean life span of population of light bulbs manufactured by a particular company is found to be 2400 hours with a standard deviation of 250 hours. A sample of 100 light bulbs produced in a lot is found to have a mean life span of 2300 hours. Test whether the population mean is less than sample mean. Assume α = 0.01.

Expert Solution

Solution-

Given information is used to calculate above test.

Test results that the null hypothesis is rejected.

So, we have enough evidence to claim that population mean is less than sample mean.

orchestra answered 1 year ago

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