An insect colony doubles in population every 10 years. Its population is reduced by 20% every 7 years. After 50 years, the population of this colony is how many times its initial population, rounded to the nearest integer.
How to solve this problem ?
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- manigraja100
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- tommywallach
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Re: population-word problem
Hey Mani,
An insect colony doubles in population every 10 years. Its population is reduced by 20% every 7 years. After 50 years, the population of this colony is how many times its initial population, rounded to the nearest integer.
How to solve this problem ?
X * 2^5 * .8^7 = X * Y
X = initial population
Y = what the question is asking for
2^5 represents 5 doublings (years 10, 20, 30, 40, 50)
.8^7 represents 7 times taking 80% (years 7, 14, 21, 28, 35, 42, 49)
Voila! (It solves to 7).
-t
An insect colony doubles in population every 10 years. Its population is reduced by 20% every 7 years. After 50 years, the population of this colony is how many times its initial population, rounded to the nearest integer.
How to solve this problem ?
X * 2^5 * .8^7 = X * Y
X = initial population
Y = what the question is asking for
2^5 represents 5 doublings (years 10, 20, 30, 40, 50)
.8^7 represents 7 times taking 80% (years 7, 14, 21, 28, 35, 42, 49)
Voila! (It solves to 7).
-t
2 posts Page 1 of 1