Answer:
The best point of estimate for the true mean is:
Since the time can't be negative a good approximation for the confidence interval would be (0,5.248) minutes. The interval are tellling to us that at 95% of confidence the average late time is lower than 5.248 minutes.
Step-by-step explanation:
Information given
represent the sample mean for the late time for a flight
population mean
represent the population deviation
n=76 represent the sample size
Confidence interval
The best point of estimate for the true mean is:
The confidence interval for the true mean is given by:
(1)
The Confidence level given is 0.95 or 95%, th significance would be 
and 
. If we look in the normal distribution a quantile that accumulates 0.025 of the area on each tail we got 
Replacing we got:
Since the time can't be negative a good approximation for the confidence interval would be (0,5.248) minutes. The interval are tellling to us that at 95% of confidence the average late time is lower than 5.248 minutes.
=[(sinx/cosx)/(1+1/cosx)] + [(1+1/cosx)/(sinx/cosx)]
=[(sinx/cosx)/(cosx+1/cosx)]+[(cosx+1/cosx)/(sinx/cosx)]
= [sinx/(cosx+1)] + [(cosx+1)/sinx]
= [sin^2x+(cosx+1)^2] / [sinx (cosx+1)]
= [2+2cosx] / [sinx(cosx+1)]
=[2(cosx+1)] / [sinx (cosx+1)]
= 2/sinx
= 2 cscx
(I think this will be helpful for you. if you can see the picture, it has more detail in it.)
Answer:
D
Step-by-step explanation:
We know that if angles x and y are complementary, then sin(x)=cos(y).
This means the measures of the angles have to add to 90 degrees, which is satisfied by the fourth option.
Distance from point C to point D: same x coordinate, 4-1=3; 3 units
Distance form point D to F: same y coordinate, 5-2=3
Perimeter is the measure of all sides
3+3+3+3=12
Solution: A. 12 units
