How far from an airport can an airplane fly and return in 8 hours, if it's outgoing speed is 160 km per hour and it's returning speed is 240 km per hour

speed = distance/time

total time is 8 hours

outgoing speed is 160 km per hour,

so time = d/160

returning speed is 240 km per hour,

so time = d/240

d/160 + d/240 = 8

3d/480 + 2d/480 = 8

5d/480 = 8

5d = 480 (8)

5d = 3840

d=3840/5

d=768

answer: so the distance is 768 km

T = 8 h

v1 = 160 km/h

v2 = 240 km/h

mmc 160 e 240 = 80

s = 80*8

s = 640 km