Big plane

[DEvans]

Please help me; I don't know where to begin. Big plane. A six passenger plane cruises at 180 mph in calm air. If the plane flies 7 miles with the wind in the same amount of time as it flies 5 miles against the wind. then what is the wind speed?

Rate Distance Air
180 mph 7 miles Calm
5 miles Against the wind

Thank you

 

[Denis]

Please help me; I don't know where to begin. Big plane. A six passenger plane cruises at 180 mph in calm air. If the plane flies 7 miles with the wind in the same amount of time as it flies 5 miles against the wind. then what is the wind speed?
Rate Distance Air
180 mph 7 miles Calm
5 miles Against the wind
Thank you

The 7 miles is NOT in calm air: it's with the wind.

Let w = wind speed
Then 180+w is speed with wind, 180-w is speed against wind ; OK?

The standard formula for travelling stuff is:
speed = distance divided by time (s = d / t);
like if you travel 200 miles in 4 hours, then speed = 200/4 = 50 mph

So, with your problem, we have:
180 + w = 7 / t : with wind
180 - w = 5 / t : against wind

I'll let you solve that.