Question

A bulb can either be on or off. A board contains 20 bulbs connected to a randomization circuit that lights up a random sequence every time it is turned on. What is the probability that all the lights will be switched on?

Answer 1

The chance that any given bulb is on is equal to 1/2.  The chance that all twenty bulbs are on at the same time is $(\frac{1}{2}) ^{20} = \frac{1^{20}}{2^{20}} = \frac{1}{1048576}$

Answer 2

Answer: 1/1048576 C for Plato!