Two coins are thrown at the same time, find the probability that different sides will fall on the coins.
In this case, there are 2 incompatible options, in which different sides will fall out on the coins:
A) 1O – 2P;
B) 1P – 2O;
Where 1, 2 – coins, O – heads, P – tails.
Their total probability can be calculated as the probability of the sum of inconsistent events P (C):
P (C) = P (A) + P (B).
The probability of variant A is calculated as the product of the probabilities of independent events (throwing of 2 coins):
P (A) = p1 * (1 – p2),
Where p1 is the probability of the first coin falling heads, (1 – p2) – the probability of the second coin falling tails.
Let’s calculate the probability of event B:
P (B) = (1 – p1) * p2,
Where (1 – p1) is the probability of the first coin hitting tails, p2 is the probability of the second coin falling heads.
Let’s determine the probability of the desired event:
P (C) = p1 * (1 – p2) + (1 – p1) * p2;
P (C) = 0.5 * (1 – 0.5) + (1 – 0.5) * 0.5 = 0.5.