Let the number of boys in the class be 'x' and the number of girls be 'y'.
Given that the average mass of the class is 52.5 kg, we can write the equation:
(50x + 54y)/(x + y) = 52.5
Multiplying both sides of the equation by (x + y):
50x + 54y = 52.5(x + y)
Expanding and rearranging the equation:
50x + 54y = 52.5x + 52.5y
52.5y - 54y = 52.5x - 50x
-1.5y = 2.5x
Dividing both sides by -1.5:
y = (2.5/1.5)x
The ratio of the number of boys to girls is therefore:
x : y = x : (2.5/1.5)x = 1.5 : 2.5
Simplifying the ratio:
x : y = 3 : 5
Therefore, the ratio of boys to girls in the class is 3 : 5.
The average mass of class is 52.5 if the average mass of the boy only in class is 50kg and that of girls is only is 54kg find ratio of number of boys to that of girls in class
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