solve
an airplain flew for 4 hours against a head wind of 40km/h. on the return flight the same wind was now a tail wind and the fight took 3 hours. find the speed of the airplain in sill air

Question

anonymous · Answer

First lets assume that the velocity of the airplane is v

anonymous · Answer

And also we assume that the velocity of the wind is w

anonymous · Answer

S= d/t
s - 40 = d /4
S + 40 = d / 3

anonymous · Answer

(v-w)4=(v+w)3

anonymous · Answer

D = 4s -160
D = 3s + 120
therefore,
4s -160 = 3s + 120
s = 120 + 160
s = 280 km / hr

anonymous · Answer

Now in place of w just put the value 40 and solve the equation for v