Answer:

And the critical value for the significance level used is:

Since the calculated value is less than the critical value we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the College graduation status and cola preference are independent
Step-by-step explanation:
For this case we want to test the following hypothesis:
Null hypothesis: College graduation status and cola preference are independent
Alternative hypothesis: College graduation status and cola preference are dependent
For this case we got a calculated statistic of:

And the critical value for the significance level used is:

Since the calculated value is less than the critical value we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the College graduation status and cola preference are independent
His conclusion wouldn't be valid because he didn't apply them on the same day. So, Brand A if applied first would be ahead of brand B which was applied 5 days later. Hope this helped!
Sam painted 3
ellie painted 2x3, so she painted 6
6+3=9
together they painted 9 pictures
168/3 = 56
<em>Therefore, Chad is driving the car in 56 mph.</em>
672/56 = 12
<em>Therefore, Chad drives 672 miles in 12 hours.</em>
308/11 = 28
<em>Therefore, Chad drives 28 miles per gallon of gas.</em>
672/28 = 24
<em>Therefore, Chad uses 24 gallons of gas to drive 672 miles.</em>
X = 2
4x + 8 = 16
-8 -8
----------------
4x= 8
-- --
4 4
------------
x=2