Define probability. Apply the term to a coin toss.

Probability is a number that reflects the likelihood of happening of a particular event.

Explanation:

Let 'E' be an event

and the no. of times the desired outcome appeared be 'm'

and the total no. of outcomes be 'n'.

Then,

P(E) = m/n

In the case of a coin, there are 2 possible outcomes; Heads and Tails

The probability of getting Heads is 1/2 and the probability of getting Tails is also 1/2.