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Sample Problems

In a petri dish, the amount of bacertia increases at a rate proportional to the amount of bacteria present. After 1 day day there are 300 bacteria present and after three days there are 800 bacteria present.

  1. How many bacteria are present intially?
  2. How many bacteria are there after 5 days?

Carbon-14 has a half-life of 5750 years. If intially there are 100 grams of carbon-14, how many grams are left after 2875 years?