Answer:
12 1/4
Step-by-step explanation:
(7 + X) × 8 - 4 × X = 56
 7 + X × 8 - 4 × X = 56
 7 + 8X - 4 × X = 56
 7 + 8X - 4X = 56
 7 + 4X = 56
 4X = 56 - 7
 X = 49/4
 X = 12 1/4
 
        
             
        
        
        
Answer: 554
Step-by-step explanation:
If prior population proportion is known, then the formula to find the sample size is given by :-

As per given description, we have
p= 0.1
E=0.025
Critical z-value for 95% confidence : 
Then, 

Hence, the minimum sample size required = 554.
 
        
             
        
        
        
Answer:
The second and fourth option
Step-by-step explanation:
In order for two lines to be perpendicular they must intercept each other and their slope must be the opposite inverse; ex:  the negative inverse is 4 (multiplying by -1 and flipping the fraction)
  the negative inverse is 4 (multiplying by -1 and flipping the fraction)
 
        
             
        
        
        
Answer:
the best way is to follow the law, sales tax is not subject to discount by the seller. 
Step-by-step explanation:
both ways result in the same outcome:
improper way, discount after tax
$50+$5(tax)=$55, after discount $55-$11(20%)=$44
proper way, discount before tax
$50-$10(20%)=$40+$4(tax)=$44