If the median of the distribution given below is 28.5, find the values of x and y.

Explanation

`because` 5+x+20+15+y+5=60
`therefore` x+y=15 … (i)
`because` Median is 28.5 which lies in class 20-30
`therefore` Median class will be 20-30
`therefore` l=20, `C_f`=cumulative frequency of the class preceding median class =5+x , f=20,h=10,N=60.
`because` Median `=l+((N/2-cf)/f)xxh`
`=20+((30-5-x)/20)xx10=28.5` (given)
`rArr (25-x)/2=8.5 " " therefore x=25-17=8 therefore y=7`
`therefore` x=8,y=7