It takes twelve minutes to load a certain video on a cellphone, and fifteen seconds to load that same video on a laptop. If the two devices were connected so that they operated in concert at their respective rates, how many seconds would it take them to load the video, rounded to the nearest hundredth?  Choose one.
A) 13.32  B) 13.87  C) 14.25  D) 14.69  E) 14.92
The laptop can load the video at a rate of 1/15 of the video per second.   The phone can load the video at a rate of 1/(60*12) = 1/720 of the video per second.   The combined rate is 1/15 + 1/720 = 49/720 of the video per second.   The time required to load the video is 720/49 = 14.69 seconds.   The answer is 14.69.
<result>D</result>
It takes twelve minutes to load a certain video on a cellphone, and fifteen seconds to load that same video on a laptop. If the two devices were connected so that they operated in concert at their respective rates, how many seconds would it take them to load the video, rounded to the nearest hundredth?