According to the US government 68 of American adults weigh m

According to the US government, 68% of American adults weigh more than they should. A dietician, Dr. Christiansen, maintained a theory that drinking 8 or more glasses of water a day was associated with not being overweight. She obtained a random sample of 580 American adults who consumed 8 or more glasses of water a day, weighed each adult, and classified each one as overweight or not. Using the goodness-of-fit test, determine if 68% of the adults in the sample were overweight assuming that 350 adults in the sample were determined to be overweight.

Solution

According to the US government, 68% of American adults weigh more than they should. A dietician, Dr. Christiansen, maintained a theory that drinking 8 or more glasses of water a day was associated with not being overweight. She obtained a random sample of 580 American adults who consumed 8 or more glasses of water a day, weighed each adult, and classified each one as overweight or not. Using the goodness-of-fit test, determine if 68% of the adults in the sample were overweight assuming that 350 adults in the sample were determined to be overweight.

Goodness of Fit Test

observed

expected

O - E

(O - E)