The shortest route from London to Edinburgh is 400 miles.
A lorry is expected to take 10 hours to travel this route.
The lorry actually travels by a different route which increases the distance by 15%, but it still arrives in 10 hours.
By how many more mph than the expected speed does the lorry travel?

Respuesta :

Answer:

The lorry travels by 6 mph more than the expected speed.

Step-by-step explanation:

Velocity formula:

Velocity is distance divided by time, that is:

[tex]v = \frac{d}{t}[/tex]

Shortest route:

400 miles in 10 hours, which means that [tex]d = 400, v = 10[/tex]. So

[tex]v = \frac{d}{t} = \frac{400}{10} = 40[/tex]

In mph.

The lorry actually travels by a different route which increases the distance by 15%, but it still arrives in 10 hours.

Distance is multiplied by 100% + 15% = 115% = 1.15, so:

[tex]d = 1.15*400 = 460[/tex]

Then

[tex]v = \frac{d}{t} = \frac{460}{10} = 46[/tex]

46 mph

By how many more mph than the expected speed does the lorry travel?

46 - 40 = 6 mph

The lorry travels by 6 mph more than the expected speed.