An Environmental Scientist Obtains a Sample of Water from an Irrigation

question 12

Multiple Choice

An environmental scientist obtains a sample of water from an irrigation canal that contains a certain type of bacteria at a concentration of 5 per milliliter. Find the mean number of bacteria in a 4-milliliter sample.

• A)2.2
• B)4.5
• C)20
• D)5

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Definitions:

Nominal Level

The most basic level of measurement that categorizes data without implying any quantitative order or degree of difference between the categories.

Median

The middle value in a data set, separating the higher half from the lower half, providing a measure of central tendency that is not influenced by extreme values.

Central Tendency

A statistical measure that identifies a single value as representative of an entire distribution of data, such as the mean, median, or mode.

Mean

The arithmetic average of a set of numbers, calculated by adding them together and dividing by the count of numbers.