SOLUTION: Two mathematics classes in Year 12 general maths course sat for some assessment task and some results are shown below: Class 1: Number of students=25 and average mark is 52% Cl

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Question 770242: Two mathematics classes in Year 12 general maths course sat for some assessment task and some results are shown below:
Class 1: Number of students=25 and average mark is 52%
Class2: Number of students=20 and average mark is 70%
What is average mark for the course?
PS. I calculated the answer to be 61 but apparently that is incorrect. This was shown by:
52 plus 70 divided by 2
Answer by ramkikk66(644) (Show Source):
You can put this solution on YOUR website!

Class 1: Number of students=25 and average mark is 52% Class2: Number of students=20 and average mark is 70% What is average mark for the course? Ans: You cannot just take the overall average as 52 plus 70 divided by 2, because the number of students in each class is different. Average = total number of marks / number of students. Therefore total marks = Number of students * average. Class1: Average = 52, students = 25, so total = 52*25 = 1300 Class2: Average = 70, students = 20, so total = 70*20 = 1400 Overall average for the course = Total marks of both the classes / total students of both the classes = Hope you got it :)