Question

A passenger plane left Paris and flewnorth at an average speed of 255 km/h.Sometime later a jet left flying in the samedirection but at an average speed of 340km/h. After flying for nine hours the jetcaught up with the passenger plane. Howlong did the passenger plane fly before thejet caught up?

Answer 1

We need to first find the distance that the jet flew before catching up to the passenger plane. To do that we need to use the average speed formula, which states that the speed is the division between the distance travelled by the time elapsed. We have:

`\begin{gathered} v=(d)/(t) \\ d=vt \\ d=340\cdot9=3060\text{ km} \end{gathered}`

Since the passanger plane was travelling at a constant speed to find the time it was travelling, we need to use the distance calculated above and solve for t.

`\begin{gathered} t=(d)/(v) \\ t=(3060)/(255)=12\text{ h} \end{gathered}`

The passenger plane was travelling for 12 hours.