document.write( "Question 460883: A convenience store asked every 21st person who entered the store for a week, their opinion of the automatic checkout machines. Is this an unbiased sample? Give a reason for your conclusion. \n" ); document.write( "

Algebra.Com's Answer #316518 by richard1234(7193) $\"\"$ $\"About$

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From the standpoint of one who has never taken statistics, I would say it is unbiased because the feedback from the customers should have no correlation with the customers' positions in line. \n" ); document.write( "

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