In the absence of any other data from you, this is what I can suggest.
ASSUMING that all entries in each column start in Cell 1, you can have
this format:
Column A -- enter the name of the traveller
Column B -- enter the room rate
Column C -- number of days for room reservation
Column D -- enter the tax rate
Column E -- enter this formula,
* =B1*C1*(1+D1)*
and copy down until your range requirements are met. This formula will
give the cost of the room for the traveller entered in Column A.