Face of coin has either head or tail. Therefore when we toss the coin, the outcome is either head or tail.
The total possible outcome for the event will be 2.

P(E)= Number of outcomes favourable to E / Number of all possible outcomes of the experiment .

Probability of getting head P(E)
P (head) = $1/2$
Probability of getting tail P(E)
P(tail) = $1/2$


Probability of getting at least one head if 2 coins are toss simantenously
Solution Number of all possible outcome => Possible outcome of tossing of 1st coin x possible outcome of tossing of 2nd coin.
= 2x2 = 4 .

Possible outcome are (H,H),(H,T),(T,H),(T,T)
Number of possible outcome of getting atleast 1 head = 3.
Probability of getting at least one head P(H)= $3/4$