If three coins are tossed simultaneously, the probability

If three coins are tossed simultaneously, the probability of getting at least one head is

Let probability of getting atleast one head = P(H) then P(at least one head) = 1 – P (no head)
⇒ P(H) = 1– P(all tails)
But in all cases, 2³ = 8

∴ P(H) = 1 -		1	=	7
		8		8

Alternately: Probability of getting at least one head