HHHT HTHH HHTT HHTH HTHT HTTH HTTT TTTH THTT TTHH TTHT THTH THHT THHH What is the probability that at least three coins land facing tails up?

5/16

Step-by-step explanation:

As you can see in the 16 given possible outcomes, in 5 of them at least 3 coins land facing up. Since there are 16 outcomes in total, the probability that at least three coins land facing up is 5/16. Hope this helps!

18

step-by-step explanation:

draw the shape and you will see that f and k are actually at adjacent vertices (points of the hexagon that are neighboring).   so find the distance between (1,2) and (4,2).   that is easy since (1,2) and (4,2) is just a vertical distance to count, which is 3.   it is a regular polygon which means all sides are congruent.   you have 6 sides (hexa) so multiply 6 by 3 to receive 18.