Math miscellaneousHard
Question
The average marks of boys in a class is 52 and that of girls is 42. The average marks of boys and girls combined is 50. The percentage of boys in the class is
Options
A.40
B.20
C.80
D.60
Solution
52x + 42y = 50 (x + y)
2x = 8y
⇒
and 
∴ % of boys = 80.
2x = 8y
⇒
and ∴ % of boys = 80.
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