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and thus
Can you see what to do now?
Hi Leroy. The average score for all students would be the total of everyone's scores divided by the number of people. The idea behind the question is this: The average is calculated by dividing the total score by the number of people, so if you know the average and the number of people, you can find the total score. Similarly, if you know the average and you know the total score, you can find the number of people. Thus, if you know any two of the three figures (total, average, people), you can determine the missing figure. Figure 1: The number of people is 50. Figure 2: The total of everyone's scores can be calculated. It is the total of the juniors' scores plus the total of the seniors' scores.
Fact 3: Since you know the number of people (Figure 1) and the total score (Figure 2), you can divide to find the average overall score. Hope this helps,  


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