Answer:
x = 6
Step-by-step explanation:
The area of a triangle is equal to the base times the height divided by two. In this case, the base is 6 (or x, it doesn't really matter) and the height is x (or 6, it doesn't matter). That means that the area of this triangle is equal to 6 * x divided by 2, which is also equal to 18. we can say that 6x/2 = 18, meaning that 6x = 36, so x = 6.
 
        
             
        
        
        
X = 4/7 = 0.571 I believe so
        
                    
             
        
        
        
Answer:
 
And we can find this probability with the following difference and using the normal standard table or excel we have:
 
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".  
Solution to the problem
Let X the random variable that represent the variable of interest of a population, and for this case we know the distribution for X is given by:
 
  
Where  and
 and  
We are interested on this probability
 
And the best way to solve this problem is using the normal standard distribution and the z score given by:
 
If we apply this formula to our probability we got this:
 
And we can find this probability with the following difference and using the normal standard table or excel we have:
 
 
        
             
        
        
        
Answer:
0.29
Step-by-step explanation:
I used a calculator