The chart below shows the amount spent by three U.S. airlines to fly one available seat one mile in the fourth quarter of 2000. $\begin{array} { | l | l | l | l | }
\hline \text { Airline } & \text { United } & \text { American } & \text { SouthWest } \
\hline \text { Cost } & 11.3 \text { cents } & 11.0 \text { cents } & 7.8 \text { cents } \
\hline
\end{array}$ Suppose that, on a 3000-mile New York-Los Angeles flight, United, American and SouthWest flew a total of 190 empty seats, costing them a total of $60,900. If United had three times as many empty seats as American, how many empty seats did each of these three airlines carry on its flight

A)United: 130
American: 40
SouthWest: 30

B) United: 120
American: 30
SouthWest: 40

C) United: 30
American: 40
SouthWest: 120

D) United: 120
American: 40
SouthWest: 30

E) United: 120
American: 30
SouthWest: 30

Question

The chart below shows the amount spent by three U.S. airlines to fly one available seat one mile in the fourth quarter of 2000. $\begin{array} { | l | l | l | l | } 
\hline \text { Airline } & \text { United } & \text { American } & \text { SouthWest } \
\hline \text { Cost } & 11.3 \text { cents } & 11.0 \text { cents } & 7.8 \text { cents } \
\hline
\end{array}$   Suppose that, on a 3000-mile New York-Los Angeles flight, United, American and SouthWest flew a total of 190 empty seats, costing them a total of $60,900. If United had three times as many empty seats as American, how many empty seats did each of these three airlines carry on its flight 
 
A)United: 130
American: 40
SouthWest: 30

B) United: 120
American: 30
SouthWest: 40

C) United: 30
American: 40
SouthWest: 120

D) United: 120
American: 40
SouthWest: 30

E) United: 120
American: 30
SouthWest: 30

Quizplus · Accepted Answer

Let the number of empty seats for American be $x$. Therefore, United had $3x$ empty seats. The total number of empty seats is 190, so $3x + x + \text{SouthWest's empty seats} = 190$, which simplifies to $4x + \text{SouthWest's empty seats} = 190$. Given the total cost of $60,900 for 190 empty seats over a 3000-mile flight, we calculate the cost per seat per mile and match it with the given costs for each airline to determine the distribution of empty seats. United's cost is 11.3 cents, American's is 11.0 cents, and SouthWest's is 7.8 cents. By calculating and distributing the total cost among the airlines based on their costs and the number of empty seats, we find that United had 120 empty seats, American had 40, and SouthWest had 30.

The Chart Below Shows the Amount Spent by Three U