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A culture contains 12,000 bacteria. After an hour the count is 25,000. Find the number of bacteria after 3 hours.

  • Math -

    let's assume the growth of bacteria is "almost" continuous
    so number = initial value e^(kt) where k is a constant

    so 12000 e^(1k) = 25000
    e^k = 2.0833333...
    k = ln 2.083333.. =.733969

    number after 3 hrs = 12000 e^(3(.733969)) = 108506.9 or
    109,000 to the nearest thousand

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