A researcher records the following body mass index (BMI)scores for a group of participants: 28.4 1.6 (M SD).Participants who score between 25 and 30 on this scale are categorized as overweight.What percentage of participants fell in this category?
A).4834
B).1753
C).8413
D).8247

Question

A researcher records the following body mass index (BMI)scores for a group of participants: 28.4  1.6 (M  SD).Participants who score between 25 and 30 on this scale are categorized as overweight.What percentage of participants fell in this category?
A).4834 
B).1753 
C).8413 
D).8247

Quizplus · Accepted Answer

To calculate the percentage of participants who fell in the overweight category (BMI between 25 and 30), we need to first calculate the standard deviation above the mean for a BMI of 25 and 30. Using the formula z = (X - M) / SD, we get:
z(25) = (25 - 28.4) / 1.6 = -2.125
z(30) = (30 - 28.4) / 1.6 = 1
Next, we look up the proportion of participants who fall between these two z-scores in a standard normal distribution table, which is 0.8242. Multiplying by 100 gives us 82.42%, which we round up to 82.47%. Therefore, the correct answer is D.

A Researcher Records the Following Body Mass Index (BMI)scores for a Group