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If the median of the distribution given below is $28.5$, find the values of $x$ and $y$.
Class: 0-10 10-20 20-30 30-40 40-50 50-60 Total
Frequency: 5 $x$ 20 15 $y$ 5 60
Class: 0-10 10-20 20-30 30-40 40-50 50-60 Total
Frequency: 5 $x$ 20 15 $y$ 5 60
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Correct table (I) (1
frac{1}{2} Mark)
Median Class = $20-30$ (II) (1/2 Mark)
$\therefore 28.5 = 20 + \frac{10}{20} (\frac{60}{2} - x - 5)$ (III) (1 Mark)
$\Rightarrow x = 8$ (IV) (1/2 Mark)
As, $x + y + 45 = 60$ (V) (1 Mark)
$\Rightarrow 8 + y = 15$
$\therefore y = 7$ (VI) (1/2 Mark)
frac{1}{2} Mark)
Median Class = $20-30$ (II) (1/2 Mark)
$\therefore 28.5 = 20 + \frac{10}{20} (\frac{60}{2} - x - 5)$ (III) (1 Mark)
$\Rightarrow x = 8$ (IV) (1/2 Mark)
As, $x + y + 45 = 60$ (V) (1 Mark)
$\Rightarrow 8 + y = 15$
$\therefore y = 7$ (VI) (1/2 Mark)