Explain briefly why a sample survey is usually preferred over census survey? ?

it's because a sample survery is like a rough draft, that people can use and turn it in to get an easy 100 grade also... A survey based on a portion of the population is called a sample survey. A sample survey is preferred over a census for the following reasons: Conducting a census is very expensive because the size of the population is usually very large.

i don't get what you mean

explanation:

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