A simple guide to theory and statistics

Question

Mathematics

I’m doing a test for absenteeism, I don’t want to read big books, who will advise a simple and visual aid for solving problems like: “There are 5 white and 4 black balls in the first urn, and 7 white and 4 black balls in the second urn. 1 is taken out randomly from the first urn balls, and from the second - 4 balls. Find the probability that among the drawn balls:
a) all balls are of the same color;
b) only three white balls;
c) at least one white ball."
It is desirable and necessary in Russian.

Answer 1

Wentzel .

Answer 2

Gmurman Theory of Probability and Mathematical Statistics.
The book is not small, but the tasks of the type you indicated can be solved if you read the first hundred pages.
And as for me, there are no small books on TViMS in the trailer.