For a relief work, a family of 10 members contributed the following amounts (in Rs):
150, 200, 500, 350, 500, 250, 700, 320, 1004, 500 
Find the median, mean and mode.

Mean = Sum of all observation / total no. of  observation
          =150 + 200 + 500+ 350 +500 +250 +700 +320 +1004 +500 /10     
          =4474 / 10
          = Rs. 447.4 

Median = middle observation ( in ascending order )
             = 150 , 200 , 250 , 320 , 350 , 500 , 500 , 500 , 700 , 1004 
                  350 and 500 are the middle observations
             =350 + 500 / 2
             = Rs . 425
           
Mode =  maximum occurring observation ( in ascending order )
          =  150 , 200 , 250 , 300 , 350 , 500 , 500 , 500 , 700 , 1004    
              500 is the most occurring observation  ( 3 times )
            Therefore - Rs . 500 is the mode