Answer:
a
The number is
![= 10](https://img.qammunity.org/2021/formulas/biology/college/6cgdo974r7pqu74f6gbumwtt4geovopa97.png)
b
The sample mean is = 3.2
The population mean is = 3
The sample mean is greater than population mean
Explanation:
From the question we can see that the number of technicians is
![n=5](https://img.qammunity.org/2021/formulas/mathematics/middle-school/cst4mnn2bni634cxl5ndw0lwh2ahv0w2h4.png)
Generally we can obtain the number of sample without replacement of size two that is possible using this formula
![^n C_r](https://img.qammunity.org/2021/formulas/mathematics/college/tye9lfqhbtvl999lkj5us05zxzxaka10yu.png)
This denote Combination which is mathematically represented as
where ! denotes factorial
So substituting 5 for n and 2 for r
No of samples without replacement of size 2
![= (5!)/(2!(5-2)!)](https://img.qammunity.org/2021/formulas/mathematics/college/291o53tqn3e2j0f6x1od0vxoer4hqf1pfi.png)
![= 10](https://img.qammunity.org/2021/formulas/biology/college/6cgdo974r7pqu74f6gbumwtt4geovopa97.png)
The sample mean of the 10 samples are shown on the first uploaded image
The population means is mathematically evaluated as
![(2+ 1+3 + 5+ 4)/(5) = 3](https://img.qammunity.org/2021/formulas/mathematics/college/y6xr5jimzvdhg66hl4ij1hwh2qu3nrcth9.png)
From the calculation on the on the table for sample mean and the population mean calculation we see that
the sample mean is greater than population mean