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In: Statistics and Probability

the mean weight of loads of rock is 47.0 tons with a standard deviation of 8.0...

the mean weight of loads of rock is 47.0 tons with a standard deviation of 8.0 tons. if 24 loads are chosen at random for a weight check, find the probability that the mean weight of those loads is less than 46.5 tons. assume that the variable is normally distributed.

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Expert Solution

Solution :

Given that ,

mean = = 47.0

standard deviation = = 8.0

n = 24

=   = 47.0

= / n = 8.0/ 24 = 1.63

P( < 46.5) = P(( - ) / < (46.5 - 47.0) /1.63 )

= P(z < -0.31)

Using z table

= 0.3783

orchestra answered 3 years ago
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