14 x 10 base for concrete?

Hi ya, i have a 14 x 10 base that needs filling with concrete as i am doing it myself so i need a rough idea how much aggregate i need an cement and what mixture do i put this in as also i have some broken paving slabs in the bottom.looking for about six inches deep as its only for my green house to go on.as need as much info as possible please. cheers all.xxx