The number of different ways to order N-many items can be calculated using something called “N-factorial” which is written as “N!”.
For three songs, that is three-factorial 3! many ways, and the definition of factorial means that this equals 3!=3x2x1=6 ways to order the songs… so randomly shuffling to the correct order would occur 1/6 of the time (about 16.7% of the time).
For four songs, 4!=4x3x2x1=24 so shuffling into the correct order has a 1/24 chance of happening (4.2% chance).
For five songs, 5!=5x4x3x2x1=120… so 1/120 (0.8%).
…For 14 songs, that 14!=14x13x12x11x10x9x8x7x6x5x4x3x2x1=87,178,291,200 amounts to ~87-Billion… so 1/87178291200 is crazy small.
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As for “Why does the factorial math describe the number of ways to shuffle something?” you gotta think about it in reverse.
There’s only one place to put the first song. 1
You can put the second song either before or after that. (1)x2
You can put the third song either before the other two, in between, or after. (1×2)x3
And so on!
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