Using the query below add the following columns/fields:

TotalInvoice --- sum of all invoices group by VendorState, VendorCity

CalculatedAvgInvoice - TotalInvoice / InvoiceCount

SELECT VendorState, VendorCity, COUNT(*) AS InvoiceQty, AVG(InvoiceTotal) AS InvoiceAvg

FROM Invoices JOIN Vendors

ON Invoices.VendorID = Vendors.VendorID GROUP BY VendorState, VendorCity

ORDER BY VendorState, VendorCity;