Six planes leave the airport at equal intervals. the first plane leaves at 8: 45 am and the last plane leaves at 10: 15 am. at what time does the third plane leave?

Dean and karlene get paid to write songs. dean is paid a one-time fee of $20 plus $80 per day. karlene is paid a one-time fee of $25 plus $100 per day. write an expression to represent how much a producer will pay to hire both to work the same number of days on a song.