In 2002 the mean age of an inmate on death row was 40.7 years with a...

In 2002 the mean age of an inmate on death row was 40.7 years with a standard deviation of 9.6 years. A sample of 32 current death row inmates shows a mean age of 38.9 years. Does this indicate that the mean age of death row inmates is less than in 2002?

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Expert Solution

Solution :

Given that,

mean = = 40.7

standard deviation = = 9.6

n = 32

= 40.7

= / n = 9.6 / 32=1.697

P( < 38.9) = P[( - ) / < (38.9-40.7) /1.697 ]

= P(z <-1.06 )

Using z table

= 0.1446

probability= 0.1446

yes this indicate that the mean age of death row inmates is less than in 2002

orchestra answered 1 year ago

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