Problem 9-8 (modified). The height of adult males in a particular city is normally distributed, with mean 69.5 in. and standard deviation 2.65 in. When a random sample is taken of size 20, find (1) the standard error of Xbar

Complete Question

Problem 9-8 (modified). The height of adult males in a particular city is normally distributed, with mean 69.5 in. and standard deviation 2.65 in.

When a random sample is taken of size  20, find (1) the standard error of Xbar

(2) the probability that Xbar falls within .5 in. of the true mean

Probability=

1

2

Step-by-step explanation:

From the question we are told that

  The true  mean is  

  The standard deviation is  

    The sample size is n =  20

Generally the standard error of Xbar is mathematically represented as

=>  

=>  

Generally for   to fall within 0.5 of the true mean the must be within

=>  

=>  

or  

=>    

=>    

Generally the probability that   fall with 0.5  of the true mean is mathematically represented as

=>  

=>  

From the z table the probability of  (  Z    < 0.844)  and   (  Z    < -0.844)  is  

and

So

=>  

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m

answer:  

step-by-step explanation:

odd numbers are only divisible by 1 and itself.

even numbers are divisible by more than 1 and itself.

for example 6 is even because it is divisible by more than 1 and its self. 1 x 6= 6 ; 2 x 3= 6

and 7 is odd because only 7 x 1 equals seveb