Q.If the median of the given data is 32, determine the values of \( x \) and \( y \) when the total frequency is 100.
Class Interval0-1010-2020-3030-4040-5050-60
Frequency10x2530y10

The frequency distribution table of the given class:
Class IntervalFrequencyCumulative Frequency (Less than type)
0-101010
10-20\(x\)10+\(x\)
20-302535+\(x\)
30-403065+\(x\)
40-50\(y\)65+\(x+y\)
50-601075+\(x+y=n\)
Here, \( n = 100 \) (Given).
According to the condition, \( 75 + x + y = 100 \)
Or, \( x + y = 25 \) ---- (i)

Again, since the median \( = 32 \), The median class is (30-40).
โˆด Median formula: \[ = l + \left[\cfrac{\cfrac{n}{2} - cf}{f}\right] \times h \] [Here, \( l = 30 \), \( n = 100 \), \( cf = 35 + x \), \( f = 30 \), \( h = 10 \)]
\[ = 30 + \left[\cfrac{50 - (35 + x)}{30}\right] \times 10 \] \[ = 30 + \cfrac{15 - x}{30} \times 10 \] \[ = 30 + \cfrac{15 - x}{3} \]
According to the condition, \[ 30 + \cfrac{15 - x}{3} = 32 \] Or, \[ \cfrac{15 - x}{3} = 2 \] Or, \[ 15 - x = 6 \] Or, \[ -x = -9 \] Or, \[ x = 9 \]
Substituting \( x \) in equation (i), \[ 9 + y = 25 \] Or, \[ y = 16 \]
โˆด The required values are \( x = 9 \), \( y = 16 \).
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