Answer:
25
Step-by-step explanation:
144/60 = 2.4
60/2.4 = x
x = 25
 
        
             
        
        
        
Answer:
Yes
Step-by-step explanation:
First, suppose that nothing has changed, and possibility p is still 0.56. It's our null hypothesis. Now, we've got Bernoulli distribution, but 30 is big enough to consider Gaussian distribution instead. 
It has mean μ= np =  30×0.56=16.8 
standard deviation s = √npq
sqrt(30×0.56×(1-0.56)) = 2.71
So 21 is (21-16.8)/2.71 = 1.5494 standard deviations above the mean. So the level increased with a ˜ 0.005 level of significance, and there is sufficient evidence.
 
        
             
        
        
        
Procedures can also be called methods because they are like steps and rules that you can follow.
        
             
        
        
        
The answer is:  [D]:  " <span>(1, 0, 0), (0, –2, 0), (0, 0, 6) " .
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