The weight of newborn babies are normally distributed with a mean of 7.62 pounds and a...

The weight of newborn babies are normally distributed with a mean of 7.62 pounds and a standard deviation of 0.61 pounds. If the weight of 22 newborn are randomly selected, what's the probability that their mean weight is more than 7.23 pounds? Round to 4-decimal places

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Expert Solution

Solution :

Given that,

mean = = 7.62

standard deviation = = 0.61

n=22

= =7.62

= / n = 0.61 / 22 = 0.13005

P( >7.23 ) = 1 - P( <7.23 )

= 1 - P[( - ) / < (7.23 -7.62) /0.13005 ]

= 1 - P(z <-2.9988 )

Using z table

= 1 - 0.0014

= 0.9986

probability=0.9986

orchestra answered 1 year ago

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