# Blog

### Are there more even or odd numbers?

Are there more even or odd numbers? Natural or rational? Rational or real? All questions…

### Why are elections unfair?

Every election is a little unfair. What are the most common reasons for this unfairness?

### How to calculate the effectiveness of vaccinations?

Even though the vaccine works and protects people from disease, more vaccinated people may die than unvaccinated people. Let's explain why this is so.

### What is 1 + 2 + 5 - 0?

Every once in a while a similar puzzle makes the rounds on social media. Let's explain how to solve similar math examples once and for all.

### The millennium problem: P vs. NP

There are seven mathematical problems that have been identified as so difficult and interesting that the Clay Mathematics Institute has named them the *problems of the millennium*, and the solver of each will be awarded one million dollars. One of the problems also touches on computer science and is called the P versus NP problem.

### Trachtenberg's method of fast addition

### We calculated one hundred trillion Pi numbers

### Occam's Razor

Occam's Razor is a method of logical decision making that tells us that if we have two different explanations for a phenomenon, we should prefer the simpler one.

### Average speed

### Dilution of solutions

### Why the seasons change

Why do the seasons change, or why is it summer in the northern hemisphere when it is winter in the southern hemisphere

### The Seven Bridges of Königsberg

People living in the town of Kralovec have been solving a riddle for a long time: the river Pregola flows through the town of Kralovec, forming two islands. There are seven bridges across the river to the islands. Is it possible to cross all the bridges in one Sunday walk, but only once each?