Ireally need to know how to solve this problem because i'm completely lost.

Two variables, x and y, vary inversely, and x=12 when y=4. what is the value of y when x=3?

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.

Find the missing dimension extra points