A researcher is interested in determining the mean energy consumption of a new compact florescent light bulb. She takes a random sample of 41 bulbs and determines
that the mean consumption is 1.3 watts per hour with a standard deviation of 0.7.
When constructing a 97% confidence interval, which would be the most appropriate
value of the critical value?

A) 1.936
B) 2.072
C) 2.250
D) 2.704
E) 2.807

The most appropriate  value of the critical value is 2.289.

Step-by-step explanation:

We are given that a researcher takes a random sample of 41 bulbs and determines  that the mean consumption is 1.3 watts per hour with a standard deviation of 0.7.

We have to find that when constructing a 97% confidence interval, which would be the most appropriate  value of the critical value.

Firstly, as we know that the test statistics that would be used here is t-test statistics because we don't know about the population standard deviation.

So, for finding the critical value we will look for t table at (41 - 1 = 40) degrees of freedom at the level of significance will be .

Now, as we can see that in the t table the critical values for P = 1.5% are not given, so we will interpolate between P = 2.5% and P = 1%, i.e;

So, the critical value at a 1.5% significance level is 2.289.

the difference between a number and 5 is -2.

step-by-step explanation:

notice that the equation you are given has -2 (negative 2) on the right side, not 2. when you subtract 5 from a number n, you are finding the difference between the number and 5.

the difference between a number and 5 is -2.