Question
In class ‘X’, the number of girls is 60% of the number
of boys. Class ‘Y’ has 20% fewer boys than class ‘X’, and the total number of students in class ‘Y’ is 30% more than that in class ‘X’. What is the ratio of number of girls in class ‘X’ to that in class ‘Y’?Solution
ATQ,
Let the number of boys in class ‘X’ = 100x
Then, number of girls in class ‘X’ = 0.60 × 100x = 60x
Number of boys in class ‘Y’ = 0.80 × 100x = 80x
Total students in class ‘Y’ = (100x + 60x) × (130/100) = 208x
Number of girls in class ‘Y’ = 208x – 80x = 128x
Required ratio = (60x):(128x) = 15:32
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