Return date of an action

Hi, I have a gantt chart which has columns headed by dates

A B C D E F
1 10/12 17/24 24/12 31/12 1/7
2 Do A
3 Finish B
4 Start C
5
6
7

I would like to put a formula in colum F to show the date that the action in
the row will be completed by. The real worksheet has 52 columns in it so
using an IF statement isn't an option. Each row will only have one entry in
it.

Thanks for any help

Ben
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