Ms. Stewart teaches three science classes. Her students are freshmen and sophomores. Her student data are shown in the relative frequency table.

\begin{tabular}{|c|c|c|c|c|}
\hline & Biology & Chemistry & \begin{tabular}{l}
Physical \\
science
\end{tabular} & Total \\
\hline Freshman & 0.15 & 0.1 & 0.2 & 0.45 \\
\hline Sophomores & 0.2 & 0.25 & 0.1 & 0.55 \\
\hline Total & 0.35 & 0.35 & 0.3 & 1.0 \\
\hline
\end{tabular}

Which statement is false?

A. [tex]$30 \%$[/tex] of her students are in physical science.
B. [tex]$45 \%$[/tex] of her students are freshmen.
C. [tex]$25 \%$[/tex] of her students are in chemistry.
D. [tex]$35 \%$[/tex] of her students are in biology.



Answer :

To determine which statement is false, we will analyze each given statement using the information provided in the relative frequency table.

Relative Frequency Table:
[tex]\[ \begin{tabular}{|c|c|c|c|c|} \hline & Biology & Chemistry & \begin{tabular}{l} Physical \\ science \end{tabular} & Total \\ \hline Freshman & 0.15 & 0.1 & 0.2 & 0.45 \\ \hline Sophomores & 0.2 & 0.25 & 0.1 & 0.55 \\ \hline Total & 0.35 & 0.35 & 0.3 & 1.0 \\ \hline \end{tabular} \][/tex]

Now, we will break down and verify each statement:

Statement A: [tex]$30\%$[/tex] of her students are in physical science.

According to the table, the total fraction of students in physical science is given as 0.3, or 30%. Hence, statement A is true.

Statement B: [tex]$45\%$[/tex] of her students are freshmen.

From the table, the total fraction of freshmen is 0.45, or 45%. Therefore, statement B is correct.

Statement C: [tex]$25\%$[/tex] of her students are in chemistry.

Looking at the table, the total fraction of students in chemistry is 0.35, or 35%. Statement C claims that 25% of the students are in chemistry. This statement, therefore, does not align with the data provided in the table. Hence, statement C is false.

Statement D: [tex]$35\%$[/tex] of her students are in biology.

From the table, the total fraction of students in biology is 0.35, or 35%. Therefore, statement D is true.

Conclusion:

Comparing all the statements with the table, it is clear that statement C is the one that is false. It inaccurately states the percentage of students in chemistry.

So, the false statement is:
C. [tex]$25 \%$[/tex] of her students are in chemistry.