Suppose that a certain website claims that it averages 4.7 hours of downtime per month. (Downtime is time that the site is not available.)
In a random sample of 17 months, the average downtime was 4.9 hours per month, with a standard deviation of 0.5 hours per month. What is the z-value rounded to the nearest hundredth? Is there enough evidence to reject the claim?

The z-value rounded to the nearest hundredth is -1.64

There is no enough evidence to reject the claim.

Step-by-step explanation:

A certain website claims that it averages 4.7 hours of downtime per month.

No. of samples = n = 17

Mean =

Standard deviation =

Formula:

Z =−1.64

Z critical at 90% is 1.65

Since Z calculated < Z critical

So, there is no enough evidence to reject the claim.

step-by-step explanation:

i think something is missing in your question because y-1=(x-12) would not pass through the point (-4,-3). because if you replace x by -4 your are supposed to find y=-3 which is not the case her. if you replace x by -4 you find =-15.

i assume the right equation is y-1=1/4*(x-12) because this one is passing through both your points (if you are interested to know how i found that out i can tell you).

in this equation if i replace x by -4 i find y=-3 and if i replace x by 12, i find y=1 so the line representing this equation is passing through those 2 points.

then the standard form of the equation is finding an expression of y in function of x

y-1=1/4*(x-12)

y=x/4-3+1

y=x/4-2

hope that .

do you confirm there was a mistake in the question?