Let a Be the Set of All Strings of Decimal

question 55

Short Answer

let A be the set of all strings of decimal digits of length five. For example, 00312 and 19483
are strings in A.
-How many strings in A have exactly one 5?

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Definitions:

Longitudinal Design

A research strategy that involves repeated observations of the same variables over short or long periods of time.

Cross-sectional Design

is a research methodology that examines data from a population, or a representative subset, at a specific point in time, often used to identify patterns or relationships.

Special Education

Tailored educational services designed to meet the unique needs of students with disabilities, ensuring they receive appropriate support to achieve educational success.

Acceleration

The provision of special programs that allow gifted students to move ahead at their own pace, even if this means skipping to higher grade levels.