Answer:
0.8762 or 87.62%
Step-by-step explanation:
Since our mean is μ=14.3 and our standard deviation is σ=3.7.  If we're trying to figure out what percentage is P(10 ≤ x ≤ 26) equal to we must first calculate our z values as such:

Our x value ranges from 10 to 26 therefore let x=10 and we obtain:

If we look at our z-table we find that the probability associated with a z value of -1.16 is 0.1230 meaning 12.30%.
Now let's calculate the z value when x = 26 and so:

Similarly, we use the z-table again and find that the probability associated with a z value of 3.16 is 0.9992 meaning 99.92%.
Now we want to find the probability in between 10 and 26 so we will now subtract the upper limit minus the lower limit in P(10 ≤ x ≤ 26) therefore:
0.9992 - 0.1230 = 0.8762 
or 87.62%
 
        
             
        
        
        
Let x be the old price 
X= 1200$
The price decreased 20% after 1 year to become price y : 
Y= 0.8x
 = 0.8 (1200)
 = 960$
In the year after y also decreased 20% to be price y’:
Y’= 0.8y
 = 0.8 (960)
 = 768 $
The price y’ then decreased 20% to become price y’’:
Y’’ = 0.8 y’
 = 0.8 (768)
 = 614.4 $
Then the price will be 614.4 $ after 3 years 
        
                    
             
        
        
        
If your trying to figure out (x) then the answer would be 7 because 7 times 2 is 14 and then 14 minus 3 would be 11
        
             
        
        
        
The answer is X=19/2 y=10