Find the mean of the data set: 9 4 7 3 10 9

Alicense plate is to consist of 44 digits followed by 55 uppercase letters. determine the number of different license plates possible if the first and second digits must be? odd, and repetition is not permitted.

Any is very appreciated! (picture is provided below)not sure how to do this at all won't lie

Which steps could be part of the process in algebraically solving the system of equations, y+5x=x^2+10 and y=4x-10