Calculating Number of Students in Second Class: Average Score Statistics

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SUMMARY

The discussion revolves around calculating the number of students in a second class based on average scores from two classes. Class one has 30 students with an average score of 80, while class two has an average score of 70, leading to a combined average of 74. The correct calculation reveals that the second class contains 45 students. Participants clarified the importance of using the total number of students in the combined classes for accurate calculations.

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Homework Statement



Two classes made a test.
In one class there were 30 students, and the average score was 80.
In the second class, the average score was 70.
The average of both classes was 74.
How many students were tested in the other class?

Homework Equations


The solution is 45 students

The Attempt at a Solution


Attached. I'm getting a minus, clearly I'm off :/

Can anyone clue me in?
 

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You are dividing by 2, where instead it should be the total number of students in the combined classes i.e. 30+x
 
Ah... I see the errors of my ways. Earlier I did 30x and got 1.11, I forgot that's not the total number of students..my bad. Thank you much.
 

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