Note: Same Answer With Normal
Distribution!
•
Group 1 = 833 and 797 ppm
•
Mean
±
std dev = 815
±
25 ppm (3.1%)
•
Group 2 = 602, 621, and 645 ppm
•
Mean
±
std dev = 623
±
22 ppm (3.5%)
•
Two-sided p < 0.0028. (< 1/360 chance
that the means are the same)