How to Use Drop Down Results to Add Multipliers to Existing Sums

Good Afternoon!

Thank you kindly for all the work you do on this forum. It has definitely come in handy in learning, although I am still on the basics.

I am looking to use some drop down text results to apply some multipliers to some computer disk space numbers.

There would be a starting number, likely calculated from some previous sums. Then, basically the user should select one of three options from a dropdown. The values of the dropdown would be listed in another sheet. If they pick Option A then the number stays the same. If they select Option B then the number gets multiplied by 1.5. If they take Option C then it gets multiplied by 2.5.

Then it would place the answer in another cell. I would like to do this in a few drop downs so I imagine if you could show me your thoughts for one or two rows, I can repeat the process for others.

I've attached a sample workbook, any suggestions would be appreciated. In the sample, I've created a few rows that have drop boxes (with the values on another sheet) and then the cells where the numbers should ideally be displayed.

Thank you in advance,

*Edit* Also little typo in the sample workbook, E10 should read E7