Quantitative Literacy Practice Exam 2026 – Comprehensive Preparation Guide

The standard deviation is a statistical measure that quantifies the amount of variation or dispersion in a set of data values. When applied to mean rainfall, the standard deviation indicates how much individual rainfall measurements vary from the average (mean) rainfall. A lower standard deviation means that the rainfall amounts are closer to the mean, showing little variability, while a higher standard deviation suggests that there is a wide range of rainfall amounts, indicating greater variability.

Thus, in the context of rainfall, the standard deviation provides insight into how consistent or inconsistent rainfall amounts are over a given time period. This information is valuable for understanding climatic conditions, agricultural planning, and water resource management. The other options do not accurately capture this concept; while they may pertain to aspects of rainfall, they lack the specific focus on variability that is represented by the standard deviation.