The speed of the plane is 420 miles per hour and the speed of the wind is 10 miles per hour.
Answer:
I only know English, so that's perfect :P
Step-by-step explanation:
I'm going to guess... that "Herman" is really "headwind" and that this jet is flying into ( headwind) and with ( tailwind) the same wind... so the same velocity wind ( note I used the physics term velocity for the speed of the wind b/c the wind also has to have a direction... and we are saying it's direction and it's speed are constant)
so take the difference of the two distances... 1290 - 1230 = 60
we now know... that the difference in distance traveled is 60 miles, so 1/2 of that is what's gained or lost , by a tailwind or a headwind, so 30 miles is gained or last flying into the wind or with the wind.
also this is in 3 hours , how convenient, 30 / 3 = 10
the wind is 10 MPH
there fore.... the jet could fly 1260 miles in 3 hours with out any wind or
d = rt where d= distance , r= rate ( think speed) and t = time ( of course [ofc] )
1260 = r * 3 hours
420 = r
the jets speed is 420 MPH
