General Math
posted by SAPPHIRE .
IF ONE CLERK CAN PROCESS 75 PIECES OF MAIL IN 2 AND A HALF HOURS, HOW LONG WILL ITTAKE EIGHT CLERKS TO PROCESS 1620 PIECESOF MAIL IF ALL OF THEM WORK AT THIS SAME RATE?

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If one clerk can process 75 pieces of mail in 2.5 hours, he/she can process 75/2.5=30 pieces of mail every hour.
With 1620 pieces of mail, and 8 clerks, it will take 1620/(8*30)=6.75 hours.