Query Resulting error

[Trimurthy]

hi,
      i am working with mysql 5.1.36 and i wrote the following query.

   select total,quantity*price from sales where total != quantity*price and 
salesid=122;

   OUT PUT:
    
   total        quatity*price
  330.46       330.46 

here quantity is 15.5 and price is 21.32

both the values and data types are double(total,quantity and price). can 
anyone tell me why this is happening.    

             Normal   0               false   false   false      EN-US   
X-NONE   AR-SA                                                              
                                                                            
                                                                            
                                                                            
                                                                            
                                                                            
                                                                      
Thanks & Kind Regards,
TRIMURTHY