To make things simple instead of using decimals and its easier to read
Answer:
The value of the test statistic is z = -0.877.
Step-by-step explanation:
Testing the difference in mean time spent on housework between husbands and wives.
At the null hypothesis, we test if there is no difference, that is, the subtraction of the means is 0:

At the alternate hypothesis, we test if there is a difference, that is, the subtraction of the means is different from 0.

The test statistic is:

In which X is the sample mean,
is the value tested at the null hypothesis, and s is the standard error.
0 is tested at the null hypothesis:
This means that 
For the wives the mean was 7 hours/week and for the husbands the mean was 4.5 hours/week. The standard deviation of the differences in time spent on house work was 2.85.
This means that 
What is the value of the test statistic for testing the difference in mean time spent on housework between husbands and wives?



The value of the test statistic is z = -0.877.
This is how I would factor it
Answer:
•0.5
Step-by-step explanation:
We'll assume the dilation was done at the origin point, so it was done evenly.
Since the k point went from (10,0) to (5,0), we know it was reduced... so the scale factor has to be below 1. A scale factor means the size wasn't changed and a dilation/scale factor larger than 1 means it was enlarged.
So, we take the new X-value (5) and divide it by the original X-value (10).
Scale factor = 5/10 = 1/2... so 0.5