Answer:
30%
Step-by-step explanation:
If the price went up to 65 from 50, that is an increase of 15. 15 is 30% of 50.
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.

Answer:
32.5 m
Step-by-step explanation:
A=Bh/2
A=13x5/2
A=65/2
A=32.5