Duration of Activity & Resource not coming same!!!!!

What do you mean not coming the same? Is the resource unit the same as activity duration * remaining Unit/time?
Can you elaborate more?

Actually I am having activities. for example

Acivity ID----------Original Duration-------------- Activity Name
Sub001-------------------10 Days----------------------Substructure

I asssigned resources(BOQ pay items) for this activity for example.
Excavation - 100m3
Backfilling - 50 m3
This is what showing in gantt chart.
But in my resource assignments window duration for the above resources showing as follows
Resource Name--------- Original Duration-----Budeget Quantity
Excavation----------------------9.56 Days-------------100 m3
Backfilling ------------------------10 Days--------------50 m3

Why the duration for the resources & Acivity duration coming differnt in the above case?

John,
The only way to check that is on Activity Window-> Activity Detail-> Resources tab
Right Click and select customise resource column then under duration double click Original duration, under dates double click Planned Start and Planned Finish. Your planned date duration maybe originally 9.56 but change to 10 but your settings in Project Window-> Detail-> Calculation tab-> Activities (link Budget and At Completion for non started Activities is not tick)
Note: Don’t forget to show the time.