Question

(1 point) Samples were collected from two ponds in the Bahamas to compare salinity values (in parts per thousand). Several samples were drawn at each site.

Pond 1: 37.36, 37.32, 37.45, 36.72, 37.03, 37.71, 37.01

Pond 2: 39.05, 38.66, 38.51, 38.89, 38.53
Use a 0.050.05 significance level to test the claim that the two ponds have the same mean salinity value.

(a) The test statistic is

Answer 1

Solution:

We have

X	Y	X​​​​​​2	Y​​​​​​2
37.16	39.05	1395.7696	1524.9025
37.32	38.66	1392.7824	1494.5956
37.45	38.51	1402.5025	1483.0201
36.72	38.89	1348.3584	1512.4321
37.03	38.53	1371.2209
37.71		1422.0411	1484.5609
37.01		1369.7401
=260.6	=193.64	=9702.418	=7499.511

The sample mean is computed as