Answer:
85
Step-by-step explanation:
Order of operations rules (PEMDAS) govern here.  Anything inside parentheses must be done first, followed by exponentiation, mult. and div., and add. and subtr. last.
Add 2+5 first:    5 + 2*{(7)*5 + 5}
Perform the work shown inside the brackets {  and  }:  5 + 2*{40}
Perform the indicated mult.:  5 + 80
Finally, add:  85
 
        
                    
             
        
        
        
Answer:
Step-by-step explanation:
We are given the letters:
2
We write the possible permutations of 3 letters from the given list:
3
Because order is not important in a combination we cross out the duplicate pairs:
4
 
        
                    
             
        
        
        
Answer:
(a) 0.9412
(b) 0.9996 ≈ 1
Step-by-step explanation:
Denote the events a follows:
 = a person passes the security system
 = a person is a security hazard 
Given:

Then, 

(a)
Compute the probability that a person passes the security system using the total probability rule as follows:
The total probability rule states that: 
The value of P (P) is:

Thus, the probability that a person passes the security system is 0.9412.
(b)
Compute the probability that a person who passes through the system is without any security problems as follows:

Thus, the probability that a person who passes through the system is without any security problems is approximately 1.
 
        
             
        
        
        
Answer:
D
Step-by-step explanation: