There are 6 things 1 2 3 4 5 6 There are 3 at a time So 6!(things) / (6-3)! (things-how many at a time) 6!/(6-3)! Or 6!/3! ! Means multiply all below that number so 6×5×4×3×2×1/ 3×2×1
30×4×3×2×1/3×2×1 You can simplify 3×2×1 since they are both on top and bottom they cancel out 30×4= 120