The mean weight of trucks traveling on a particular section of I-475 is not known. A state highway inspector needs an estimate of the mean. He selects a random sample of 49 trucks passing the weighing station and finds the sample mean is 15.8 tons. The population standard deviation is 3.8 tons. What is the 95 percent confidence interval for the population mean

The 95 percent confidence interval for the population mean is between 14.736 tons and 16.864 tons.

Step-by-step explanation:

We have the population's standard deviation, so we can find the normal confidence interval.

We have that to find our level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of .

So it is z with a pvalue of , so

Now, find the margin of error M as such

In which is the standard deviation of the population and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 15.8 - 1.064 = 14.736 tons

The upper end of the interval is the sample mean added to M. So it is 15.8 + 1.064 = 16.864 tons

The 95 percent confidence interval for the population mean is between 14.736 tons and 16.864 tons.

t = 3

step-by-step explanation:

put t = 3 in this expression :

(3²-1)(3²-2)(3² - 3)(3² - 4) = 8×7×6×5 = 56×30 = 1680

a net is a diagram that shows a “flattened” view of a solid. in a net, each face and base is shown with all of its dimensions. a net can also serve as a pattern to build a three-dimensional solid.

a pyramid is a three-dimensional object with a base that is a polygon and triangular faces that meet at one vertex.

" the net of a triangular pyramid consists of four triangles. the base here we are given of the pyramid is a equilateral   triangle, and the lateral faces are also triangles "