I have been reading about probabilities as I am heading back to school next week. This image is represented by 300 columns and 361 lines. That's 108,300 squares or pixels. Each pixel is filled with one of the 256 colors described in the palette of colors below.
Probability = 1 / 256 * 1 / 256 * 1 / 256 ... for 108,300 times.
That's a really small value - extremely close to zero. That's one reason we haven't observed monkeys drawing the Queen of England till now.