Cost price of 10,000 pairs of slacks is C=$19.66 and marked price is M=$21.83.
Then, the selling price of 10,000 pairs of slacks is
So, the selling price of 10,000 pairs of slacks is $41.49.
Therefore, the selling price of each pair of slacks is
So, the selling price of each pair of slacks is $0.004149.