What is the missing number?
MATH PUZZLE: Can you replace the question mark with a number?Correct answers: 61
The first user who solved this task is Djordje Timotijevic.
#brainteasers #math #riddles
Saul DushmanBorn 12 Jul 1883; died 7 Jul 1954 at age 70. Russian-American physical chemist, a world leader in vacuum science and technology, a GE assistant director of research and author of several standard scientific textbooks. One example is Scientific Foundations of Vacuum Technique (1922). It is very readable and he gets to the hows and whys things work the way they do. One of the true classics, it was completely revised in 1961 by his colleague James Lafferty. Using a formula he derived, Dushman calculated the conductances for cylindrical tubes based on their measured dimensions and produced the table which he included in the book that is still used to design a vacuum system. |