Thread: Plz Solve

There are 10 coins. 6 coins showing head. And 4 showing tail. Each coin was randomly flipped (not tossed) seven times successively.after flipping the coins are 5 heads 4 tails one is hided the hided coin will have what.

Originally Posted by bharathlece

There are 10 coins. 6 coins showing head. And 4 showing tail. Each coin was randomly flipped (not tossed) seven times successively.after flipping the coins are 5 heads 4 tails one is hided the hided coin will have what.

The way this question reads it will be heads with probability 0.5 and tails with
probability 0.5. But we must suspect that something else was intended, if so
the intention has been lost somewhere.

RonL

on which basis ur going to say that head and tail has a probability of 0.5

plz explain in detail.

Originally Posted by bharathlece

on which basis ur going to say that head and tail has a probability of 0.5

plz explain in detail.

That the coins are fair, and that flipping even once randomises a coins
orientation. So knowledge of the orientation of the other coins tell you nothing
about the orientation of the last coin, and after they have all been flipped
at least once their orientations are unrelated and randomised.

RonL

RonL

Hi:

I am inclined to believe this to be a "trick question", its deception being drawn from its ambiguous delivery. At first reading, it seemed (to me) that the coins were gathered up from their initial positions as 6 H and 4T, and reflipped. The trickster, expecting the trickee to assume just that, further expects such assumption to confound his unsuspecting victim. But no mention of a reflip was made. That being the case, the hidden coin is facing heads up.

Regards,

Rich B.