Hi, Newbie here and not good at code, hope you can help.

I have 2 tables, there is a lot more to the tables that is not relevant so I have presented a simplified version just to explain what i need.

1st table has 2 columns a list of containers in the 1st and how much is in each container in the 2nd

2nd table has 3 columns, in the 2nd column i can select multiple containers from the 1st table in a single box, 3rd column i want it to display the total contents of the selected containers in the previous box.

example Table 1

1 cont1 50L

2 cont2 175L

3 cont3 25L

4 cont4 50L

example Table 2

1,3 75L

2,4 125L

Hope this makes sense

Cheers

Vince