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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
THERE ARE 49 STEPS. HE CLIMBS HALFWAY, WHICH IS STEP 25. HE HEARS THE BIRD SINGING ON STEP 33. HE PICKS UP THE PEBBLE ON THE 21ST STEP AND TOSSES IT ON THE 22ND STEP. THE REMAINING 27 STEPS ARE TAKEN THREE AT A TIME WHICH IS 9 PACES (3 STEPS X 9 PACES = 27 STEPS)
IT WOULD TAKE 47 DAYS TO COVER HALF OF THE LAKE, AS THEY DOUBLE IN SIZE EVERY DAY
THE JAR WILL BE HALF FULL IN 59 MINUTES. A MINUTE LATER, IT WILL DOUBLE AND WILL FILL THE JAR
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
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