The average age of students of a class is 15. | vedclass

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(D) Let the number of boys be $x$ and the number of girls be $y$.Sum of ages of boys $= 16.4x$.Sum of ages of girls $= 15.4y$.The average age of all t

Vedclass · Accepted Answer

$2:3$

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(D) Let the number of boys be $x$ and the number of girls be $y$.Sum of ages of boys $= 16.4x$.Sum of ages of girls $= 15.4y$.The average age of all the students is given by the total sum of ages divided by the total number of students:$\frac{16.4x + 15.4y}{x + y} = 15.8$.Multiplying both sides by $(x + y)$, we get:$16.4x + 15.4y = 15.8(x + y)$.$16.4x + 15.4y = 15.8x + 15.8y$.Rearranging the terms to group $x$ and $y$:$16.4x - 15.8x = 15.8y - 15.4y$.$0.6x = 0.4y$.Therefore, the ratio of boys to girls is $\frac{x}{y} = \frac{0.4}{0.6} = \frac{2}{3}$.Thus, the ratio is $2:3$.

The average age of students of a class is $15.8 \, \text{years}$. The average age of boys in the class is $16.4 \, \text{years}$ and that of the girls is $15.4 \, \text{years}$. The ratio of the number of boys to the number of girls in the class is:

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