# Math Help - word problem

1. ## word problem

A jet flies twice as fast as a propeller plane. On a trip 1500 miles, the propeller plane took 3 hours longer than the jet. Find the speed of each plane.

2. Originally Posted by Hapa
A jet flies twice as fast as a propeller plane. On a trip 1500 miles, the propeller plane took 3 hours longer than the jet. Find the speed of each plane.
If the propeller plane is twice as slow and it took 3 hours longer then it must've taken 6 hours, whilst the jet took 3.
1500/3 = 500 mph for the jet
1500/6 = 250 mph for the propeller plane

3. Originally Posted by Hapa
A jet flies twice as fast as a propeller plane. On a trip 1500 miles, the propeller plane took 3 hours longer than the jet. Find the speed of each plane.
Hi Hapa,

Recall that 'Distance = Rate X Time'

d = rt

t =d/r

Let p = rate of prop plane

Let 2p = rate of jet plane

Let $\frac{1500}{p}$= time for the prop plane

Let $\frac{1500}{2p}$ = time for the jet plane

The distance is constant, and since the prop plane is 3 hours behind the jet plane, the two times wll equate this way:

$\frac{1500}{p}=\frac{1500}{2p}+3$

Multiply through by 2p

3000 = 1500 +6p

6p = 1500

p = 250 mph for the prop plane

The jet travels 500 mph