Answer:
The probability that the proportion of books checked out in a sample of 412 books would differ from the population proportion by less than 4% is P=0.9255.
Step-by-step explanation:
The population's proportion is 
If we take a sample of 412 books (n=412), we have a standard deviation of the sampling distribution of:

We have to calculate the probabilty that the sample proportion will be between 0.25 and 0.33.

The answer to your question is 3
.333333.........% i cant write the little mark above it but it goes on continuosly.
Answer:
equation: y = 12x
Dr. Betz worked for 8 hours.
Step-by-step explanation:
To write the equation we'll use the form y = mx, where y represents the amount of time the Doctor worked, m is the amount of minutes it takes to treat each animal, and x is how many animals have been treated. We know the value of m is 12, so let's put that into the equation:
y = 12x
Now we have our equation. We can use it to see how long Dr. Betz worked. He treated a total of 40 animals - 20 including the shaggy dog, and 20 after the shaggy dog. let's replace x with 40:
y = 12(40)
Now solve:
y = 480
Dr. Betz worked for 480 minutes. There are 60 minutes in an hour. Divide 480 by 60 to find out how many hours Dr. Betz worked for:
480/60 = 8
Dr. Betz worked for 8 hours.