Answer:
29/100
Step-by-step explanation:
percent actually means per-hundred (cent is a.o. French for hundred).
39/1.5 = 26 km per hour
51/3 = 17 km per hour
Then you need the mean. 26+17/2 = 21.5 km per hour
Answer:
a) 
b)
c)
Step-by-step explanation:
Assuming the following question: Because of staffing decisions, managers of the Gibson-Marimont Hotel are interested in the variability in the number of rooms occupied per day during a particular season of the year. A sample of 20 days of operation shows a sample mean of 290 rooms occupied per day and a sample standard deviation of 30 rooms
Part a
For this case the best point of estimate for the population variance would be:

Part b
The confidence interval for the population variance is given by the following formula:
The degrees of freedom are given by:
Since the Confidence is 0.90 or 90%, the significance
and
, the critical values for this case are:
And replacing into the formula for the interval we got:
Part c
Now we just take square root on both sides of the interval and we got:
Answer:
Yes
Step-by-step explanation:
Use the completing the square method:
16(x^2-x)+4
=16((x-1/2)^2 - (1/2)^2)+4
=16((x-1/2)^2 - 1/4)+4
=16((x-1/2)^2) - 16/4 + 4
=16(x-1/2)^2
=4^2(x-1/2)^2
The product of two square is itself a square.