Using the relation between velocity, distance and time, it is found that:
Velocity is distance divided by time, that is:
[tex]v = \frac{d}[t}[/tex]
Flying against the wind, an airplane travels 2520 kilometers in 4 hours, that is:
[tex]v - v_w = \frac{2520}{4}[/tex]
[tex]v - v_w = 630[/tex]
[tex]v = 630 + v_w[/tex]
Flying with the wind, the same plane travels 9450 kilometers in 9 hours, hence:
[tex]v + v_w = \frac{9450}{9}[/tex]
[tex]v + v_w = 1050[/tex]
[tex]v = 1050 - v_w[/tex]
Hence, solving for the wind's speed:
[tex]630 + v_w = 1050 - v_w[/tex]
[tex]2v_w = 420[/tex]
[tex]v_w = \frac{420}{2}[/tex]
[tex]v_w = 210[/tex]
For the plane, we have that:
v = 1050 - 210 = 840.
More can be learned about the relation between velocity, distance and time at https://brainly.com/question/24316569
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