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A class teacher has the following absentees record of $30$ students of a class.
If the mean number of days a student was absent is $12$, find the values of $x$ and $y$.
If the mean number of days a student was absent is $12$, find the values of $x$ and $y$.
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Correct Table:
$x + y + 20 = 30 \Rightarrow x + y = 10$ ---(i)
$12 = \frac{224 + 10x + 22y}{30} \Rightarrow 5x + 11y = 68$ ---(ii)
Solving (i) and (ii) we get $x = 7, y = 3$
$x + y + 20 = 30 \Rightarrow x + y = 10$ ---(i)
$12 = \frac{224 + 10x + 22y}{30} \Rightarrow 5x + 11y = 68$ ---(ii)
Solving (i) and (ii) we get $x = 7, y = 3$