Formula Help: use a certain multiplier based from the product groups

Hello Everyone, I was just looking to see if I can get a little help making a formula. I have attached my excel sheet of what I am trying to do.

In Cell I21, I am trying to get excel to use a certain multiplier based from the product groups.

IF G21 ="2171" use cell B11 "2172" use B12 and so on.

This formula will help me with the 9000+ items I will have to add to it.

For the life of me I can not get it to work. If anyone has an idea of how I can do it that would be great. Thanks in advance and hope everyone is staying safe

Administrative Note:

Welcome to the forum.

We would very much like to help you with your query, however the thread title does not really convey what your request is about. Tell us what you are trying to do, not how you think it should be done.

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