Use Random-Variable Notation to Represent the Event Use Random-Variable Notation to Represent the Event That the Student

question 120

Multiple Choice

Use random-variable notation to represent the event.
-The following table displays a frequency distribution for the number of siblings for students in one middle school. For a randomly selected student in the school, let X denote the number of siblings of
The student. $\begin{array}{r|rrrrrrrr}\text { Number of siblings } & 0 & 1 & 2 & 3 & 4 & 5 & 6 & 7 \\\hline \text { Frequency } & 189 & 245 & 102 & 42 & 24 & 13 & 5 & 2\end{array}$

Use random-variable notation to represent the event that the student obtained has fewer than two siblings.

• A)\(\{ X \leq 2 \}\)
• B) \(\{ X < 2 \}\)
• C) \(\{ 0,1 \}\)
• D) \(P \{ X < 2 \}\)

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Definitions:

Teratogens

Substances or elements that lead to fetal or embryonic developmental issues or congenital anomalies.

Blastocyst

A blastocyst is an early stage in the development of an embryo, consisting of a sphere of cells surrounding a fluid-filled cavity and the cluster of cells from which the embryo will develop.

Placenta

An organ that develops in the uterus during pregnancy, supplying oxygen and nutrients to the growing baby and removing waste products.

Critical Periods

Specific timeframes in the development of an organism when it is particularly sensitive to certain environmental stimuli, leading to irreversible outcomes.