Question
A bowl contains a colony of bacteria. Every hour, the
bacteria population doubles, but immediately after doubling, a virus kills 40% of the population. After 3 hours, the population of bacteria in the bowl is found to be 4320. What was the initial population of bacteria in the bowl?Solution
Let the population of bacteria in the beginning be '100x' So, population at the end of 1st hour = 100x X 2 X 0.6 = '120x' So, population at the end of 2nd hour = 120x X 2 X 0.6 = '144x' So, population at the end of 3rd hour = 144x X 2 X 0.6 = '172.8x' ATQ: 172.8x = 4320 So, x = 25 So, population of the bacteria in the beginning = 100x = 100 X 25 = 2500
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