Answer:
His 95% confidence interval is (0.065, 0.155).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of 
.
For this problem, we have that:
95% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
The lower limit of this interval is:
The upper limit of this interval is:
His 95% confidence interval is (0.065, 0.155).
Answer: Reject the eight- ounces claim.
Step-by-step explanation:
For left tailed test , On a normal curve the rejection area lies on the left side of the critical value.
It means that if the observed z-value is less than the critical value then it will fall into the rejection region other wise not.
As per given ,
Objective : A coffee-dispensing machine is supposed to deliver eight ounces of liquid or less.
Then ,
, since alternative hypothesis is left-tailed thus the test is an left-tailed test.
the critical value for z for a one-tailed test with the tail in the left end is -1.645 and the obtained value is -1.87.
Clearly , -1.87 < -1.645
⇒ -1.87 falls under rejection region.
⇒ Decision : Reject null hypothesis.
i.e. we reject the eight- ounces claim.
The answer is 5 divided by 1/3
I'm going to assume that the room is a rectangle.
The area of a rectangle is A = lw, where l=length of the rectangle and w=width of the rectangle.
You're given that the length, l = (x+5)ft and the width, w = (x+4)ft. You're also told that the area, A = 600 sq. ft. Plug these values into the equation for the area of a rectangle and FOIL to multiply the two factors:
Now subtract 600 from both sides to get a quadratic equation that's equal to zero. That way you can factor the quadratic to find the roots/solutions of your equation. One of the solutions is the value of x that you would use to find the dimensions of the room:
Now you know that x could be -29 or 20. For dimensions, the value of x must give you a positive value for length and width. That means x can only be 20. Plugging x=20 into your equations for the length and width, you get:
Length = x + 5 = 20 + 5 = 25 ft.
Width = x + 4 = 20 + 4 = 24 ft.
The dimensions of your room are 25ft (length) by 24ft (width).
