Hi - I'm a web designer working mainly in html with a little bit of PHP but would really like to learn more about Javascript. I have a client who sells cushions and would like a little quote calculator on their web page to show customers the cost of cushions that they sell depending on size. The calculation would be (where 24 x 24 x 4 are where the customer could enter any height, length and width to determine cost):

24" X 24" x 4" = 2304. 2304 divided by 144 = 16.

16 x 3.10 = 49.60.

I have absolutely no idea where to start! Could anyone help/point me in the right direction please?

Many thanks.