one cell?

[arclight]

this is what i'm wanting to accomplish
CostX=D4
Quantity=C4
Percent=E4
Total=F4

I need CostX multiplied by a Percent, and that total added to CostX, then multiplied by the Quantity. Is there any way to get this total in one cell? Also is there a way to change the percent amount in the cell itself, without having to adjust the formula, for example if my percent is 15, and I want to bump it up to 30. Thanks in advance, and sorry if this is a stupid question I'm quite new to excel.

[mudraker]

If % figure in E4 is just a number & the cell not formated as percent then in F4 try.
=((D4*(E4/100))+D4)*C4

If E4 is formatated as percent try
=((D4*E4)+D4)*C4