Question 1206563
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Suppose a designer has a palette of 11 colors to work with, and wants to design 
a flag with 4 vertical stripes, all of different colors.

How many possible flags can be created?
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<pre>
First  vertical strip can be any of 11 colors.

Second vertical strip can be any of remaining 10 colors.

Third  vertical strip can be any of remaining  9 colors.

Fourth vertical strip can be any of remaining  8 colors.


Hence, the total number of differently colored flags is the product
of four integer numbers, starting from 11, in descending order

    11*10*9*8 = 7920.    <<<---===  <U>ANSWER</U>
</pre>

Solved.