So I am working out the odds for a lottery, picking 4 numbers between 1-35.
The equation is:
$$\mbox{odds}=\frac{35\cdot 34\cdot 33\cdot 32}{1\cdot 2\cdot 3\cdot 4}=52360$$
Yes, I can work this out on a calculator with ease.
However, how can I work this out on pen and paper, or in my head with ease?
Are there any type of methods or cheats I could use to calculate this quickly?