Can I use a formula based on a text from a drop down list in a different cell?

Hi, I have created an invoice template with a drop down list for chargeable items. I would like to have a formula which would calculate the value based on the drop down selection. I have tried to use =CHOOSE(MATCH... formula but it's not working.

I created the drop down list using data validation, data is sourced from a separate worksheet within the file. Drop down has the following text options to choose from:

• 5% deposit
• 50% deposit
• 45% balance

If I choose one of the above in cell A2, enter a value in cell A1, I would like a calculation to happen in cell B2 that will calculate 5%, 50% or 45% of A1 based on the selection in A2.

Any ideas welcome.

Many thanks