GMAT Critical Reasoning (CR) | Re: According to a research of 1000 individuals, 70% of the people who wer

Let x is the number of people who joined the Genco's weight loss program.
Total number of people who joined the Genco's weight loss program and lost an average of 4 pounds of weight in one month = 0.7x
Total number of people who did not join the Genco's weight loss program and lost an average of 4 pounds of weight in one month = (0.7*0.8/0.2) x = 2.8 x (clearly it's greater than x)

So option D

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