I am making a formula to include a description.

IE...

product price amount Cost
red fabric $1.50 4 yards =(price*amount)


thats the basics of what i am trying to do. I have made a drop down list for the amount as well if that matters. I understand the problem to be that my formula performs math on those cells by using the standard arithmetic operators (+, -, *, and /). How can i make the formula ignore the text in that field and still do the math.

Thanks in advance for any help.