An airport kept track of the number of flights that left on time for two different airlines. The data are shown in a relative frequency table.

\begin{tabular}{|c|l|l|l|}
\hline & Airline A & Airline B & Total \\
\hline Flight on time & 0.4 & 0.3 & 0.7 \\
\hline Flight not on time & 0.2 & 0.1 & 0.3 \\
\hline Total & 0.6 & 0.4 & 1.0 \\
\hline
\end{tabular}

What does the 0.2 in the yellow cell mean?

A. 20% of all the flights were on airline A and not on time.
B. 20% of airline A's flights were not on time.
C. 20% of all the flights were not on time.
D. 20% of all the flights were on airline A.



Answer :

Let's carefully analyze the given relative frequency table to understand what each cell represents. Here's the table provided:

\begin{tabular}{|c|l|l|l|}
\hline & Airline A & Airline B & Total \\
\hline Flight on time & 0.4 & 0.3 & 0.7 \\
\hline Flight not on time & 0.2 & 0.1 & 0.3 \\
\hline Total & 0.6 & 0.4 & 1.0 \\
\hline
\end{tabular}

We are interested in understanding the meaning of the 0.2 in the second row, first column, which represents flights from Airline A that were not on time.

To decipher this:

1. Total Proportion of Flights for Each Airline:
- Column "Total" indicates that 60% (0.6) of the total flights were with Airline A.
- The same column shows that 40% (0.4) of the total flights were with Airline B.

2. Proportion of On Time Flights:
- From the row labeled "Flight on time," we see that 40% (0.4) of all flights with Airline A were on time.
- Similarly, 30% (0.3) of all flights with Airline B were on time.

3. Proportion of Not on Time Flights:
- The cell in question, 0.2, falls under "Flight not on time" and "Airline A." This indicates that 20% (0.2) of all flights are flights from Airline A that were not on time.

4. Comparison with Total Flights for Airline A:
- The total proportion of Airline A flights is 60% (0.6) as per the "Total" row.
- Within this 60%, we see that:
- 40% (0.4) of the flights are on time,
- and the remaining 20% (0.2) are flights from Airline A that were not on time.

Thus, the 0.2 represents the proportion of Airline A's flights that did not leave on time. Putting it in percentage terms:
[tex]\[ 0.2 \times 100\% = 20\% \][/tex]

Therefore, the 0.2 in the yellow cell means:
[tex]\[ B. \; 20\% \; \text{of airline A's flights were not on time.} \][/tex]