a plane flies 900 miles with a tail wind, in 3 hours. It takes the same plane 4 hours to fly the 900 miles when flying against the wind. What is the planes speed in still air?

• DISTANCE=SPEED*TIME
  SPEED=DISTANCE/TIME
  SPEED1 =900/3=300MIL/HR IWITH TAIL WIND
  SPEED2=900/4=225MIL/HR AGAINST THE WIND
  SPEED IN STILL AIR=(2*S1*S2)/(S1+S2)
  =(2*300*225)/(300+225)
  =(1800)/7=257.142MIL/HR
• 9 years agoHelpfull: Yes(0) No(0)