Question
The total number of students in class X and Y is 72. The
number of students in X is 40% more than that in Y. The average marks of students in Y are 50% more than that of students in X. If the average marks of all the students in X and Y are 58, then what are the average marks of students in X?Solution
Let the number of students in class Y is x then the number of students in class X will be = 1.4a Let the average marks of students in class X is b then the average marks of students in class Y will be = 1.5b Now given, average of both the class is 58. Thus, (1.4a × b + a ×1.5b)/(a+1.4a) =58 1.4b +1.5b =58×2.4 b = (58×2.4)/2.9 b=48.
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