Suppose you're shooting with a famous archer at his range at home.
You both start shooting and all of a sudden, he says "Damn!" and stops.
You ask what's up and he pulls out all his arrows and holds them up.
All but two have tungsten points.
You offer to go get two more to make a full set and walk into his shed.
He calls out to you:
"I was refletching yesterday.
There should be a mix.
There are three arrow tubes.
One will have two tungsten arrows.
One will have two stainless
and the other will have a stainless and a tungsten point."
You walk up to the closest arrow tube and pull an arrow out. It's a tungsten point.
What are the chances that the remaining arrow in the tube is also a tungsten point?