'manpreet singh wrote:The population of a certain type of bacterium triples every 10 minutes. If the population of a colony 20 minutes ago was 100, in approximately how many minutes from now will the bacteria population reach 24,000?
I need to know a faster and quicker way to solve the problem.
We could use the formula for exponential growth:
Final Amount = Original Amount * (Multiplier)^(Number of changes)
In the problem above:
Final Amount = 24,000
Original Amount = 100
Multiplier = 3 (since the population keeps tripling)
Number of changes = x.
Plugging these values into the formula, we get:
24,000 = 100 * 3^x
3^x = 240.
Since 3� = 243, x ≈ 5.
Since the number of changes = 5, and each change takes 10 minutes, the total time needed = 5*10 = 50 minutes.
Since the starting time was 20 minutes ago, the population will reach 24,000 about 30 minutes from now.
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