Question

A biologist tranquilizes 400 wild elephants and measures the lengths of their tusks to determine their ages. Identify the population and the sample.

Answer 1

The population is all of the wild elephants.  The sample is the 400 wild elephants selected.

Answer 2

The population here refers to the all the wild elephants that are present in that particular geography. This refers to the whole universe of wild elephants present in the area,

The sample is the 400 elephants that the biologist tranquilized to mesaure the length of their tusks.

So, to conclude, population = all wild elephants present and sample = 400 elephants that were tranquilized