Task 1. In an urn, there are 8 balls, 5 of which are white. A ball is drawn from the urn 8 times, and after recording its color, it is returned to the urn. Find the probability that the white color was recorded 3 times.
Solution. Let event $A$ be the appearance of a white ball in one of the 8 draws. Then $p=5 / 8=0.625 ; q=1-p=0.375 ; n=8 ; k=3$. We need to calculate $p_{8}(3)$. According to the Bernoulli formula (19):

$$
p_{8}(3)=C_{8}^{3} \cdot 0.625^{3} \cdot 0.375^{5}=56 \cdot 0.244 \cdot 0.007=0.101
$$

Answer. 0.101 .