Question
The average number of boys in three classes is 8 more
than the average number of girls in the same three classes. The total number of girls in all the three classes is 192. If the number of boys in one class is 25% more than that in other and the number of boys in the remaining class is 18, then find the highest number of boys in a class.Solution
Let the number of boys in first class = 100x Then, the number of boys in second class = 125x the number of boys in third class = 18 total number of boys in all three classes = 100x + 125x + 18 = 225x + 18 according to the question- (225x+18)/3 = 192/3 +8 (225x+18)/3 = 64 +8 = 72 225x+18 = 216 x = 198/225 highest number of boys are in second class = 125x 125x = 198/225 × 125 = 110 highest number of boys in class = 110
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