Answer :
Answer:
• The speed of the jet in still air = 970 miles per hour
,• The speed of the jetstream = 160 miles per hour.
Explanation:
The speed of the jet against the jet stream
[tex]\begin{gathered} =\frac{2430\; miles}{3\; hours}. \\ =810\text{ miles per hour} \end{gathered}[/tex]The speed of the jet with the jet stream
[tex]\begin{gathered} =\frac{4520\; miles}{4\; hours}. \\ =1130\text{ miles per hour} \end{gathered}[/tex]• Let the speed of the jet in still air = x miles per hour
,• Let the speed of the jetstream = y miles per hour.
The speed against the jetstream = x-y
The speed with the jetstream = x-y
[tex]\begin{gathered} x-y=810 \\ x+y=1130 \end{gathered}[/tex]Add to eliminate y:
[tex]\begin{gathered} 2x=1940 \\ x=\frac{1940}{2} \\ x=970\text{ mph} \end{gathered}[/tex]Next, solve for y:
[tex]\begin{gathered} x-y=810 \\ 970-y=810 \\ y=970-810 \\ y=160\text{ mph} \end{gathered}[/tex]Thus:
• The speed of the jet in still air = 970 miles per hour
,• The speed of the jetstream = 160 miles per hour.