Question 1143996
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Any of the 7 students may seat at the chair #1        (7 options).


Any of remaining 6 students can seat at the chair #2  (6 options)


Any of remaining 5 students can seat at the chair #3  (5 options)



Thus, in all,  7*6*5 = 210 different ways (placements) are possible.     <U>ANSWER</U>
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