help with Hypothesis testing

**Hi,**

**I'm having a bit of trouble with these two questions. Am I on the right track for the first q and am i using the right formula? and any ideas on how to work out the second question. thanks**

**QUESTION 4: **

In an attempt to examine the historical difference between two investments, the return from each investment was recorded over the last 10 reporting periods. The results were:

PERIOD 1 2 3 4 5 6 7 8 9 10

INVESTMENT 1 9.2 6.0 12.5 7.0 6.7 9.4 9.4 7.1 5.7 6.6

INVESTMENT 2 6.8 7.3 11.2 8.6 10.5 9.1 6.4 7.5 0.7 2.8

Assuming the investment returns are normally distributed, can we conclude that the average rate of return for Investment 1 is greater than the average return for Investment 2 at the 5% level of significance?

For this question do I just

Calculate the differences

enter the differences

Calculate the mean difference (d)

And the standard deviation of the differences (SD)

Using the formula (t- test), find the value of t.

**t=d/(SD/n)**

**QUESTION 5: **

A weight-loss company claims that its weight-loss program is superior to its competitor. To test this claim, a group of 16 overweight male volunteers were randomly allocated to one program or the other and the weight losses over a 3-month period were recorded:

COMPANY PROGRAM 1.4 0.4 4.8 3.7 0.5 5.2 0.7 5.4

COMPETITOR'S PROGRAM 0.7 3.9 1.5 0.1 0.3 1.6 0.5 2.6

Use a suitable parametric test, with a 5% level of significance, to assess the company’s claim. Why will this be a 1-sided test? [Note that the data is not paired (matched) in this question]

what test and formula would I use for this question?

thanks