Date -Time difference

Date -Time difference

I have this code to return Days, Hours, Mins, which somehow doesn't seem to return the correct amount of hours. I have been looking at it for a while, but I am not sure where I am going wrong. 

(((((((((Task_Completed_Date_Time - Request_Date_Time)  /  (1000  *  3600  *  24))).toLong())) + " Days ") + (((((((Task_Completed_Date_Time - Request_Date_Time)  /  (1000  *  3600  *  24))).toDecimal()  -  (((Task_Completed_Date_Time - Request_Date_Time)  /  (1000  *  3600  *  24))).toLong())  *  60)).toLong())) + " Hours") + (((((((Task_Completed_Date_Time - Request_Date_Time)  /  (1000  *  3600))).toDecimal()  -  (((Task_Completed_Date_Time - Request_Date_Time)  /  (1000  *  3600))).toLong())  *  60)).toLong())) + " Mins"


Thanks in advance for your help!


Joy