
Explanation:
The question is asking for the probability that a random variable , which follows a normal distribution with a mean of 40 and a standard deviation of 14, does not lie between the values 12 and 61. To find this probability, we first calculate the standardized -scores for the given values using the formula:
For , the -score is:
For , the -score is:
Using a standard normal distribution table (Z-table), we find the probabilities for being less than -2 and greater than 1.5. The probability is approximately 0.0228, and is approximately 0.0668. Since we are looking for the probability that does not lie between 12 and 61, we are interested in the combined probability of being less than -2 or greater than 1.5.
The combined probability is calculated by adding the individual probabilities:
This gives us the probability that does not lie between 12 and 61 as 8.96%, which corresponds to option C. This question tests the understanding of how to work with probabilities in the context of a normal distribution and the use of Z-tables to find probabilities associated with specific -scores.
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