Answer:
32.6
Step-by-step explanation:
Look at the decimal in the hundredths place in 32.62
If the number is 0-4, round down. If the number is 5-9, round up.
In 32.62, the number in the hundredths place is 2. So, we round down to 32.6
So you know that 30 + 30 + w + w = P. We also know the area is 240 square feet. Divide 240 by 30 to find the width of the area. 240 / 30 = 8. w = 8. So add 30 + 30 + 8 + 8 to find that P = 76. HOWEVER, remember that George is using part of his house as a wall instead of a fence. So subtract 8 from 76 to get 68 ft. George will need 68 ft. of fencing for his dog run.
Answer:
See the proof below.
Step-by-step explanation:
For this case we just need to apply properties of expected value. We know that the estimator is given by:

And we want to proof that 
So we can begin with this:

And we can distribute the expected value into the temrs like this:

And we know that the expected value for the estimator of the variance s is
, or in other way
so if we apply this property here we have:

And we know that
so using this we can take common factor like this:

And then we see that the pooled variance is an unbiased estimator for the population variance when we have two population with the same variance.