Question

In a statistics class of 30 students, the mean score on the midterm was 72. In another class of 40 students, the mean score was 79. What was the mean score of the two classes combined?

Answer 1

Mean score of combined glasses `= 76`

Explanation:

Total score for class with `30` students and mean score of `72`
`color(white)("XXX")30xx72=2160`

Total score for class with `40` students and mean score of `79`
`color(white)("XXX")40xx79=3160`

Total number of student in combined classes
`color(white)("XXX")30+40 = 70`

Total of total class scores
`color(white)("XXX")2160+3160 = 5320`

Mean score for combine classes
`color(white)("XXX")5320 div 70 = 76`