Question:
A biologist studied the population of rats in a granary. He found the average natality was 280, average mortality was 200, immigration was 40 and emigration was 50. The net increase in population is:
A biologist studied the population of rats in a granary. He found the average natality was 280, average mortality was 200, immigration was 40 and emigration was 50. The net increase in population is:
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Population growth = (Births + Arrivals) − (Deaths + Departures)
Updated On: Jan 13, 2026
- 80
- 70
- 10
- 90
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The Correct Option is B
Solution and Explanation
Net increase in population = (Natality + Immigration) − (Mortality + Emigration)
= (280 + 40) − (200 + 50)
= 320 − 250
= 70
= (280 + 40) − (200 + 50)
= 320 − 250
= 70
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