bourne shell programming help

hey,

i have 2 files... orders and products

how do i do calculations on the order using the products ?

say if the products file is:

a123:shirt:10.00
zz123:nice shirt:19.95

and the order file is:

05/08/30 a123 10

zz123 3

Jun-3-1994 a123 2

2005.06.23 a123 2

how do i do the calculation using a shell script ??

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I will close this duplicate thread.