In the Choose Four lottery game, players choose four different numbers from 1 to 15. The order of the numbers matters, so the selection of 4-15-6-3 is different form 6-4-15-3. (1).How many possible lottery sequences are there?
If the order matters, you use permutations. If the order doesn't matter, you use combinations.
You will use permutations here. In this case, you'll use 15p4 okay?
Wait what is permutations.
In general - \(\Large \color{MidnightBlue}{\Rightarrow nPr = {n! \over (n - r)!} }\)
Oh I did something like that I'm going to draw it.
P=n!/(n-r)! 15x14x13x12x11x10x9x8x7x6x5x4x3x2x1
Yeah.
In the same way, \(\Large \color{MidnightBlue}{\Rightarrow _{15}P_{4} = {15! \over (15 - 4)!} }\)
\(\Large \color{MidnightBlue}{\Rightarrow {15! \over 11!} }\) \(\Large \color{MidnightBlue}{\Rightarrow 15 * 14 * 13 * 12 }\)
and so on and so on right
Yeah.
so 180 x 182= 32,760
Is that the answer in all together?
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