Question

A biologist studied the population of rats in a barn. He found that the average natality was 250, average mortality 240, immigration 20 and emigration 30. The net increase in populations is :
A. 15
B. `05`
C. zero
D. 10

Answer 1

Correct Answer - C
Net increase in population : (Natality + Immigration) - (Mortality + Emigration)
(250 + 20) - (240 + 30)
270 - 270 = 0