Answer:
5
Step-by-step explanation:
Mxn Matrices do not have an inverse solution for m ≠ n, so your 2x4 will not have a solution.
<span>Generally, inverting matrices is done through finding the determinant of the square matrix and then performing an operation on the matrix based on the size of the matrix. </span>
<span>Wikipedia has a good article on Matrix inversion, take a look there for more information.</span>
For the given situation we have a total of 259,459,200 permutations.
<h3>
How many permutations are?</h3>
First, how we know that it is a permutation?
Because the order matters, we aren't only selecting 8 out of the 15 people, but these 8 selected also have an order (is not the same thing to finish the race first than fourth, for example).
Then we need to find the number of permutations, to do it, we need to find the numbers of options for each of the 8 positions.
- For the first position there are 15 options.
- For the second position ther are 14 options (one runner already finished).
- For the third position there are 13 options.
- And so on.
Then the total number of permutations (product between the numbers of options) is:
P = 15*14*13*12*11*10*9*8 = 259,459,200
If you want to learn more about permutations:
brainly.com/question/11732255
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