Hello Bhutan,

The days in the duration column indicates the duration of each activity. If you need hours of the resources allocated to each task, my tip would be to use the Work column, you will find it the hours spent on each activity.

To enter the Work column, just click right on the name of any column and choose Insert Column, and then find work. Once resources are included in the activities will be calculated automatically hours.

Reference

http://canalopenproj.blogspot.com/2013/04/duracao-e-configuracoes-de-calendario.html

Hope this helps.