To test the significance difference between two population mean
A dietician investigated whether apples washed in hot water or in cold water turned brown at different rates when exposed to air. She took 13 random apples and cut each in half. She washed one half of each apple in hot water and the other half in cold water, and after that put both halves out in a tray. Her results (in hours until turning a particular shade of brown) are in the table below. At ∞_ = .01, did she see a difference between the two treatments?
|
|
Hot Water
|
Cold Water
|
|
Sample mean
|
5.50
|
4.85
|
|
Sample variance
|
2.60
|
2.00
|
a.No, since the test value -1.09 is inside the range (-3.055, 3.055).
b.No, since the test value -0.79 is inside the range (-3.055, 3.055).
c.Yes, since the test value -0.79 is inside the range (-3.012, 3.012).
d.Yes, since the test value -1.09 is outside the range (-3.012, 3.012).