Given,

The coin tossed = 1000 times

The total number of trial = 1000

Lets assum,

The event of getting head = E

The event of getting tail = F

Then,

Number of trials in which the E happens = 455

So,

Probability of E =

P (E) =

Similarly,

The probability of the event getting a tail =

P (F) =

Note: we note that P(A)+P(B) = 0.48+0.52

Therefore, A and B are the only two opposite outcomes.