I have a table containing prices of a product with the width across the
columns and length down the rows looking something like this;

25 30 35 40
25 4.60 5.20 6.35 7.10
30 5.15 6.20 7.85 8.30
35 6.15 7.50 8.30 9.20

What I am looking for is for the user to enter values in 2 cells (width and
length), and have the price returned for the product in the price cell. eg;
if the user enters width 32 and length 26 it would return 7.85 in the price
cell (it must always round up not down)

I hope you understand what I want. Thanks in anticipation.