715 miles / 11 hours = 65 mph
845 miles / 65 mph = 13 hours
It would take 13 hours to drive 845 miles.
        
             
        
        
        
47- 12 1/3 = 34 2/3
He needs 34 and 2/3 feet more of fabric
        
             
        
        
        
Answer:
(Picture)
Step-by-step explanation:
To find 60% of people you just multiply .6 with the number you are trying to find 60% of. Like 100. 100 times .6 = 60.
 
        
                    
             
        
        
        
Answer:
The standard deviation is of 8.586.
Step-by-step explanation:
For each person, there are only two possible outcomes. Either they have a genetic mutation, or they do not. The probability of a person having the mutation is independent of any other person, which means that the binomial probability distribution is used to solve this question.
Binomial probability distribution
Probability of exactly x successes on n repeated trials, with p probability.
The standard deviation of the binomial distribution is:

About 9% of the population has a particular genetic mutation.
This means that 
900 people are randomly selected.
This means that 
Find the standard deviation for the number of people with the genetic mutation in such groups of 900.

The standard deviation is of 8.586.