A small airplane flies 1160 miles with an average speed of 290 miles per hour. 2 hours after the plane leaves, a Boeing 747 leaves from the same point. Both planes arrive at the same time; what was the average speed of the 747 ?

Respuesta :

Answer:

[tex]580\text{ miles per hour}[/tex]

Step-by-step explanation:

To solve this problem, we can use the formula [tex]d=rt[/tex], where [tex]d[/tex] is distance, [tex]r[/tex] is rate, and [tex]t[/tex] is time.

Let's start by calculating how long the small airplane takes to complete the journey. The distance is 1160 miles and the rate is 290 miles per hour. Therefore, we have:

[tex]1160=290t,\\t=\frac{1160}{290}=4\text{ hours}[/tex]

Since the Boeing 747 left 2 hours after the small airplane left, the small airplane has just [tex]4-2=2[/tex] hours left of travelling time.

Therefore, to arrive at the same time as the small airplane, the Boeing 747 must cover the same distance of 1160 miles in only 2 hours. Hence, the Boeing 747's speed must have been:

[tex]1160=2r,\\r=\frac{1160}{2}=\boxed{580\text{ miles per hour}}[/tex]