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0 / 60 seg.
A scientist puts a bacteria in a petri dish at exactly noon. Every minute the bacteria divides into two and doubles in size. At exactly 1 PM the petri dish is full. At what time was the dish half full?
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Clue
YES. HE TOOK AS MUCH TIME FOR THE SECOND HALF OF HIS TRIP AS THE WHOLE TRIP WOULD HAVE TAKEN ON FOOT. SO NO MATTER HOW FAST THE TRAIN WAS, HE LOST EXACTLY AS MUCH TIME AS HE SPENT ON THE TRAIN. HE WOULD HAVE SAVED 1⁄30 OF THE TIME BY WALKING ALL THE WAY
THE DISH WAS HALF FULL AT 12.59 PM. SINCE THE BACTERIA DOUBLES EVERY MINUTE, THEN ONE MINUTE EARLIER, THE DISH MUST HAVE BEEN HALF FULL
THE JAR WILL BE HALF FULL IN 59 MINUTES. A MINUTE LATER, IT WILL DOUBLE AND WILL FILL THE JAR
IT WOULD TAKE 47 DAYS TO COVER HALF OF THE LAKE, AS THEY DOUBLE IN SIZE EVERY DAY
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