I have the following problem from a Textbook
A small plane is travelling between Windsor and Pelee Island (a distance of approx. 60 km) and is directly affected by the prevailing winds. Thus, the actual speed of the plane with respect to the ground is the speed of the plane (160 km/h) plus or minus the wind speed, w. Develop a simplified equation for the total time it takes to make a round trip if the wind speed is w.
I made my best effort to sovle this myself, but in comparing with the textbook answer-key, what I've got and what they've got don't match- and I can't really figure out why.
The textbook answer was:
My answer was:
My logical process for this question was in two steps. I know that Time is going to be distance / speed. In order to determine speed, I need to factor speed with and against the wind, which gives me the quadratic on the bottom. For my distance, I read off the question it is 60km. If it is 60km, and a round trip, the total distance must be 120km.
What am I missing that 120 is transformed into 19200. My initial guesses were a unit issue (i.e metres vs kilometres), but that doesn't make much sense to me. Since they give you the fixed distance, I don't really know what else to do here.
Any and all assistance is appreciated.