Find All Replacements (Less Than the Modulus) for the Question

question 10

Multiple Choice

Find all replacements (less than the modulus) for the question mark that make the statement true.
-7 ∙ ? ≡ 8 (mod 9)

• A) 8
• B) 5
• C) 2, 6, 7
• D)1, 3

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Definitions:

Margin of Error

A measure of the uncertainty or potential error in the results of a survey or experiment, often expressed as a plus-minus figure.

Standard Deviation

A statistical measure that quantifies the amount of variation or dispersion of a set of data values.

Mean Height

The average height of a group of individuals, calculated by summing their heights and dividing by the number of individuals.

Confidence Interval

A spectrum of values obtained from statistics of a sample, which is likely to encompass the actual population parameter at a specific probability level.