Question
In a school of 50 students, the average score in a
French exam is 72 marks, but when one student transferred out and 4 new students joined the school, the average score became 71.5 marks. What is the score of a student who has 4 marks more than the score of the student who left, if the total score of the four new students is 270 marks?Solution
ATQ, Sum of scores of class = 50 * 72 = 3600 3600 - x + 270 = 71.5 * 53 3870 - x = 3790 x = 80 Required score of the student = 80 + 4 = 84 marks
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