Question 1185833
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In a shipment of 22 smart phones, three are defective. 
How many ways can a quality control inspector randomly test six smart phones, 
of which three are defective?
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<pre>
They want you calculate the number of different sextuplets (subsets of 6 smartphones)
that contain that three defective smartphones.


Then, it is obvious, that the number of such sextuplets is equal to the number of different TRIPLETS
that you can select from 22-3 = 19 good smartphones to add them to that unique triple of
defective smartphones.


Finally,  {{{C[19]^3}}} = {{{(19*18*17)/(1*2*3)}}} = 969  is your  <U>ANSWER</U>.
</pre>

Solved and thoroughly explained.