Using arrangements and combination, it is found that there are [tex]8.65 \times 10^7[/tex] different schedules possible.
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Combination formula:
[tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by:
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
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[tex]T = C_{13,2}C_{8,2}C_{11,2} = \frac{13!}{2!11!} \times \frac{8!}{2!6!} \times \frac{11!}{2!9!} = 120120[/tex]
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[tex]6!(120120) = 720(120120) = 86486400[/tex]
A similar problem is given at https://brainly.com/question/23302762