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3 years ago

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Young's modulus is a quantitative measure of stiffness of an elastic material. Suppose that for metal sheets of a particular typ

e, its mean value and standard deviation are 75 GPa and 1.7 GPa, respectively. Suppose the distribution is normal. (Round your answers to four decimal places.)
Required:
a. Calculate P(79 <= P <= 81) when n = 25.
b. How likely is it that the sample mean diameter exceeds 81 when n = 36?

1 answer:

Marizza181 [45]3 years ago

8 0

Answer:

a) P(79 <= P <= 81) = 0.9968

b) P( X > 81 ) = 0.0002

Step-by-step explanation:

mean value = 75 GPa

standard deviation = 1.7 GPa

<u>a) Determine P(79 <= P <= 81) </u>

given that : n = 25

attached below is the detailed solution

P(79 <= P <= 81) = 0.9968

<u>b) Determine how likely the sample mean diameter will exceed 81 </u>

given that n = 36

mean diameter = 81

P( X > 81 ) = 0.0002

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