Question

A cyclist rides her bike at a speed of

Answer 1

OK so basically when converting 2 meters per second to kilometers per hour you will get 7.2 kilometers per hour. OK so times that by 4 and you will get 28.8 kilometers in 4 hours.

Answer 2

Alrighty 2 m/s

(2m/s) X (1 km/ 1000 m)  X  (60s / 1 min)  X  (60 min / 1 hr) = 7.2 km/hr

Part B:

7.2 X 4 = 28.8


Basically what I am doing is canceling out terms and replacing them with the terms I want. for example: I need to convert meters into kilometers. In my given (2 m/s) meters is on the top and my answer requires that I have km on the top. SO to convert meters into kilometers I have to put meters on the bottom and kilometers on the top. 

Hence, why I put (1 km/ 1000 m) km on top (like I want and m on bottom to cancel m). I did the same thing with converting seconds into hours.