Two sections of a class took the same quiz. section a had 15 students who had a mean score of 80, and section b had 20 students who had a mean score of 90. overall, what was the approximate mean score for all the students on the quiz? a. 84.3b. 85c. none of these d. cannot be determined

Option B. 85

Step-by-step explanation:

Two sections of a class took the same quiz.

Mean score of section A of 15 students = 80

Mean score of section B of 20 students = 90

We will calculate the approximate mean score for all the students.

The pool mean is the mean of means of two or more groups. We will find it by this formula =

                   =

                   = 85

The approximate mean score for all the students on the quiz was 85.

56.6

step-by-step explanation:

the ratio of the perimeters is equal to the scale.

the ratio of the areas is equal to the square of the scale.

34 / 20 = k

a / 19.6 = k²

substituting:

a / 19.6 = (34 / 20)²

a = 19.6 (34 / 20)²

a ≈ 56.6