An airplane can travel 380 miles into the wind in the same time that it can travel 420 miles with the wind. If the wind speed is 10 miles per hour, find the speed of the airplane without any wind.

Is this correct:
380(x-10)=420(x+10)
380x-3800=420x+4200
-420x -420x
-40x-3800=4200
+3800 +3800
-40x=8000
-40x/-40=8000/-40
x=200

is 200 miles the answer?

*I have a correction:

380(x+10)=420(x-10)

t (v-10) = 380

t(v+10) = 420

380/(v-10) = 420/(v+10)
so I get
380(v+10) = 420(v-10) yes agree

40 v = 8000
v = 200 miles/hour

Thanks

Yes, 200 miles per hour is indeed the speed of the airplane without any wind.