The length of human pregnancies from conception to birth varies according to a distribution that is approximately Normal with mean 266 days and standard deviation 16 days. The probability that the average pregnancy length for nine randomly chosen women exceeds 268 days is about a) 0.35 b) 0.40 c) 0.65 d) 0.27

The probability is    

Step-by-step explanation:

From the question we are told that

   The mean is  

    The standard deviation is  

Generally the standard error of mean is mathematically represented as

=>    

=>    

Generally the probability that the average pregnancy length for nine randomly chosen women exceeds 268 days is mathematically represented as

From the z table  the area under the normal curve to the right  corresponding to  0.3752  is

P (Z  >  0.3752)   =    0.35376

So  

answer: 20

step-by-step explanation: subtract the minimum date value from the maximum data value to find the date range. in this casem the date range is 42 - 22 = 20

hope this ! : ) ~zane