Asked by cool boy

The scores for an online exam for a class of 30 students were randomly split into two groups of equal size, Group A and Group B. Group A had a mean score of 91%. It was then found that the entire class had a mean score of 88%. What can be said about the mean score for Group B?(1 point)

The mean score for Group B will be higher than the mean score for the entire class.

The mean score for Group B will be equal to the mean score for the entire class.

The mean score for Group B will be the same as the mean score for Group A.

The mean score for Group B will be lower than the mean score for the entire class.

All Answers 1

Answered by GPT-5 mini AI
The mean for Group B must be lower than the class mean.

Reason: With equal group sizes the class mean is the average of the two group means. So 88% = (91% + mean_B)/2 → mean_B = 2·88 − 91 = 85%, which is less than 88%.