Question 1200295
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Answer:  <font color=red size=4>0.03515</font> (approximate)



Work Shown:
z = (x-mu)/sigma
z = (7.9-13.5)/3.1
z = -1.80645161290322 approximately
z = -1.81
Then use a table such as <a href="https://www.ztable.net/">this one</a> to find that
P(Z < -1.81) = 0.03515
In the link I posted, scroll down to the section labeled "How to Read The Z Table" for an example.
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