Question

Given two dependent random samples with the following results:

Population 1	$67$	$69$	$75$	$72$	$52$	$62$	$75$	$71$
Population 2	$77$	$60$	$83$	$69$	$62$	$70$	$70$	81

Can it be concluded, from this data, that there is a significant difference between the two population means? 

Let d=(Population 1 entry)−(Population 2 entry)

$d=\text{(Population 1 entry)}-\text{(Population 2 entry)}$. Use a significance level of α=0.01$\alpha =0.01$ for the test. Assume that both populations are normally distributed.

Step 2 of 5 :  

Find the value of the standard deviation of the paired differences. Round your answer to one decimal place.