Question 745893
The distribution of weights of a sample of 1,400 is symmetric and bell-shaped. According to Empirical Rule, what percent of the weights will lie
a. Between x̅-2s and x̅+2s?
Ans: At least (1-(1/2)^2) = (1-0.25) = 0.75 = 75% of the data
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b. Between x̅ and x̅+2s? 
Ans: (1/2)0.75 = 37.5%
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Below x̅-2s
Ans: 0.5-0.375 = 12.5%
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Cheers,
Stan H.