Question:
Roselin had an aquarium at her home with 10 fish in it. In a year, a fish gave birth to 7 fish. During this period, 3 adult fish had died. Roselin's father purchased 2 more pairs of fish from market for the aquarium. Later, Roselin gifted 4 fish from the aquarium to her friend. Find out the growth rate of fish in Roselin's aquarium.
Roselin had an aquarium at her home with 10 fish in it. In a year, a fish gave birth to 7 fish. During this period, 3 adult fish had died. Roselin's father purchased 2 more pairs of fish from market for the aquarium. Later, Roselin gifted 4 fish from the aquarium to her friend. Find out the growth rate of fish in Roselin's aquarium.
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Growth rate calculation must include both internal (birth/death) and external (immigration/emigration) factors if provided.
Updated On: Mar 9, 2026
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Solution and Explanation
Step 1: Understanding the Concept:
Growth rate (\(r\)) = Net increase in population / Initial population.
Step 2: Detailed Explanation:
Initial population (\(N\)) = 10.
Births = 7. Deaths = 3.
Immigration (purchased) = 2 pairs = 4 fish.
Emigration (gifted) = 4 fish.
Net Change (\(\Delta N\)) = \((7 + 4) - (3 + 4) = 11 - 7 = 4\).
Step 3: Final Answer:
Growth Rate = \(4 / 10 = 0.4\) per fish per year.
Growth rate (\(r\)) = Net increase in population / Initial population.
Step 2: Detailed Explanation:
Initial population (\(N\)) = 10.
Births = 7. Deaths = 3.
Immigration (purchased) = 2 pairs = 4 fish.
Emigration (gifted) = 4 fish.
Net Change (\(\Delta N\)) = \((7 + 4) - (3 + 4) = 11 - 7 = 4\).
Step 3: Final Answer:
Growth Rate = \(4 / 10 = 0.4\) per fish per year.
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