If X Is a Normal Random Variable with a Mean $P ( X \leq 87 )$

question 19

Short Answer

If X is a normal random variable with a mean of 78 and a standard deviation of 5, find the following probabilities:
a. $P ( X \leq 87 )$
b. $P ( X \geq 91 )$
c. $P ( X = 78 )$

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Definitions:

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Occurs when a meteoroid survives its passage through the Earth's atmosphere and impacts the surface, often resulting in craters and sometimes affecting the environment or climate.

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The event in which dinosaurs ceased to exist, primarily occurring at the end of the Cretaceous period due to mass extinction events.

Pangea

Supercontinent that began to form about 300 million years ago and broke up 100 million years later.

Land Mass

A large contiguous area of land recognized as a distinct geographical entity, not fully covered by water.