The chart above shows the distribution of letter grades for three grou

For this one, we only need to calculate the weighted average of the students in group 3.

Two students got an A, 9 got a B, seven got a C and 4 got a D, so the total number of points is 2*4 + 9*2 + 7*2 + 4*1 = 53. With 22 students in total, we get a weighted average of just under 2.5. The Answer is B.

From the chart:

2*4+9*3+7*2+4*1 / 22 (total students in group 3)

= 53 / 22
= 2 9/22 = ~2.4-2.5

B - 2.4

total of group 3 = 4*1 + 7*2 + 9*3 + 2*4 = 53
Total students 22

Mean = 53/22 = 2.4
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Answer = B. 2.4



Mean of Group 3 \(= \frac{4*1 + 7*2 + 9*3 + 2*4}{4+7+9+2} = \frac{53}{22} = 2.4\)

OFFICIAL SOLUTION:

(B) There are 4 + 7 + 9 + 2 = 22 students in group 3.

The grade distribution in group 3 was:
4 students received a grade of D.
7 students received a grade of C.9 students received a grade of B.
2 students received a grade of A.

Therefore, the sum of the grade points for group 3 is:
(4 × 1) + (7 × 2) + (9 × 3) + (2 × 4) =
4 + 14 + 27 + 8 = 53.

We can find the average grade in group 3 by dividing this sum by the number of students in group 3:
Average for group 3 = 53/22.

Performing the required division, we see that 2.4 is the closest answer choice.

The correct answer is choice (B).
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