Flying against the wind, an airplane travels 2650 kilometers in 5 hours. Flying with the wind, the same plane travels 5700 kilometers in 6 hours. What is the rate of the plane in still air and what is the rate of the wind?

\begin{tabular}{|c|c|}
\hline
Rate of the plane: & [tex]\(\square \, \text{km/h} \)[/tex] \\
\hline
Rate of the wind: & [tex]\(\square \, \text{km/h} \)[/tex] \\
\hline
\end{tabular}



Answer :

Let's solve the problem step by step.

Let the rate of the plane in still air be [tex]\( p \)[/tex] (in kilometers per hour) and the rate of the wind be [tex]\( w \)[/tex] (in kilometers per hour).

### Step 1: Establish Equations

#### Against the Wind
When traveling against the wind, the effective speed of the plane is reduced by the speed of the wind. Thus, the effective speed of the plane is [tex]\( p - w \)[/tex].

The given data tells us that the plane travels 2650 kilometers in 5 hours while going against the wind. We can express this relationship with the equation:
[tex]\[ p - w = \frac{2650}{5} \][/tex]

Simplifying, we get:
[tex]\[ p - w = 530 \][/tex]

#### With the Wind
When traveling with the wind, the effective speed of the plane is increased by the speed of the wind. Thus, the effective speed of the plane is [tex]\( p + w \)[/tex].

The given data tells us that the plane travels 5700 kilometers in 6 hours while going with the wind. We can express this relationship with the equation:
[tex]\[ p + w = \frac{5700}{6} \][/tex]

Simplifying, we get:
[tex]\[ p + w = 950 \][/tex]

### Step 2: Solve the System of Equations

We now have a system of linear equations:
[tex]\[ \begin{cases} p - w = 530 \\ p + w = 950 \end{cases} \][/tex]

We can solve these equations simultaneously.

First, add the two equations:
[tex]\[ (p - w) + (p + w) = 530 + 950 \][/tex]
[tex]\[ 2p = 1480 \][/tex]
[tex]\[ p = 740 \][/tex]

Next, substitute the value of [tex]\( p \)[/tex] back into one of the original equations to find [tex]\( w \)[/tex]. Let's use [tex]\( p + w = 950 \)[/tex]:
[tex]\[ 740 + w = 950 \][/tex]
[tex]\[ w = 950 - 740 \][/tex]
[tex]\[ w = 210 \][/tex]

### Conclusion

The rate of the plane in still air is [tex]\( 740 \)[/tex] kilometers per hour, and the rate of the wind is [tex]\( 210 \)[/tex] kilometers per hour.

[tex]\[ \begin{tabular}{|c|c|} \hline Rate of the plane: & 740 km/h \\ \hline Rate of the wind: & 210 km/h \\ \hline \end{tabular} \][/tex]