Question

A plane can fly 1020 miles in the same time as it takes a car to go 360 miles. If the car travels 110 mph slower than the plane, find the speed of the plane.

Answer 1

The speed of Plane (Sp) = 170 mile per hour

Explanation:

Given as ,

Distance travel by Plane (Dp) = 1020 miles

Distance travel by Car (Dc) = 360 miles

Time taken by Car (Tc ) = Time taken by Plane (Tp) = T hour

Let the speed of Plane = Sp mile per hour

So, Speed of Car = Sp - 110 mile per hour

Now from Distance formula , Distance = Speed × Time

Then , Dp = Sp × Tp = Sp × T

And Dc = (Sp - 100) × Tp = (Sp - 100) × T

So,
`(Dp)/(Dc)` =
`(Sp)/(Sp - 110)`

`(1020)/(360)` =
`(Sp)/(Sp - 110)`

`(51)/(18)` =
`(Sp)/(Sp - 110)`

Or, 51 ( Sp - 110) = 18 Sp

i.e 51 Sp - 5610 = 18 Sp

Or, 51 Sp - 18 Sp = 5610

Or, 33 Sp = 5610

∴ Sp =
`(5610)/(33)` = 170 mph

Hence the speed of Plane (Sp) = 170 mile per hour Answer