Easy probability question

Question

Just wanted to see if many of you guys will fall for my "made up" trap

If the coin is tossed two times, what is the probability that it will turn up head at least once. A) 1/4 B) 1/2 C) 1/6 D) 3/4 E) 1

Fig · Answer

(D) for me

P(1 twist and no head) = 1/2 That implies, P(2 twists and no head) = 1/2*1/2 = 1/4 Hence, P(2 twists and at least 1 head) = 1 - 1/4= 3/4

SimaQ · Answer

But it has a little twist in it doesn't it?

MBAlad · Answer

1 - probability of 2 tails

1-(1/2*1/2) = 3/4

anindyat · Answer

Think in this way...
possible cases are HH, HT, TH and TT

so (HH and HT and TH) / (all cases) = 3/4

arjsingh1976 · Answer

good explaination

yogeshsheth · Answer

P atone head = 1 -P(none)
P(none)=1/2*1/2=1/4

therefore required =3/4

SimaQ · Answer

You are all correct and avoided my trap, which was "at least once"

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