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To give you an exact answer we will need the number of cards, how many are AU, and other information.
In general terms, if you have AU cards younger than your AAoA, it will help your average to remove them from your report. If the AU are older than your AAoA, it will reduce your average if you remove them.
There are some products that only give the AAoA of open accounts. FICO score calculates your AAoA with both open and close accounts. In other words, your AAoA could be different.
Removing 3 AU accounts younger than your AAoA will help your AAoA, but may hurt your UTIL, it all depends how much the AUs are used and their limits.
They may be other things you can do to help your score. I don't think what is needed to remove the AUs will help that much.
EDIT: if the AU is hurting your UTIL, then it is hurting your score. Many lenders will not remove you from the reports, you may need to dispute the accounts to get the removed. I think first you need to contact the bank to be removed, don't know if you can do it or the primary should do it. Good luck.