In a school, there are 35 students in class 2A and 40 in class 2B. The mean score for class 2 in an English Literature examination is 60.0 and that for 2B in the same paper is 52.5. Find, to one place of decimal, the mean for the combined classes

Cbaidi

10 years ago

How was 4200 gotten

Hansel05

2 years ago

To find the mean for the combined classes, we'll first calculate the total score for both classes and then divide by the total number of students.

Let's denote:

n1n1​ = number of students in class 2A (35 students)
n2n2​ = number of students in class 2B (40 students)
xˉ1xˉ1​ = mean score for class 2A (60.0)
xˉ2xˉ2​ = mean score for class 2B (52.5)

Total score for class 2A: n1×xˉ1=35×60.0=2100n1​×xˉ1​=35×60.0=2100
Total score for class 2B: n2×xˉ2=40×52.5=2100n2​×xˉ2​=40×52.5=2100

Total number of students: n1+n2=35+40=75n1​+n2​=35+40=75

Total combined score: 2100+2100=42002100+2100=4200

Mean for the combined classes: 420075=56.0754200​=56.0

So, the mean for the combined classes is 56.056.0​ (Option B).

moiya

3 years ago

how do we get 4200

Ibukun017

2 years ago

how do we get 4200