Bill downloads the movieRevenge of the Avengersto his computer in 2.5 hours, using a download manager that downloads from 3 sources marked A, B and C. Each source provides download at a constant rate, but the rates of different sources are not necessarily identical. If the movie was downloaded from sources A and C alone, it would take 4 hours to complete the download. The next day, source B is available, but the other sources are inactive. How long will it take to download the trailer of the movie, a file that is 80 times smaller, from source B alone?
Choose the correct choice from the following options:
A) 6 hours and 40 minutes B) 15 minutes C) 12 minutes D) 10 minutes E) 5 minutes
Let the movie size be 400 u.   Given,A+C=4 hrs.   A+C=100 u/hr   And A+B+C=2.5 hrs or   400/2.5= 
<gadget id="calculator">  400/2.5</gadget>
<output>160</output>
160 u/hr   B alone=160-100= 
<gadget id="calculator">160-100</gadget>
<output>60</output>
60 u/hr   Trailer=80 times smaller or  400/80= 
<gadget id="calculator">  400/80</gadget>
<output>5</output>
5 u   B will take 5/60 hrs or 5 minutes.   Ans 5 minutes
<result>E</result>
Bill downloads the movieRevenge of the Avengersto his computer in 2.5 hours, using a download manager that downloads from 3 sources marked A, B and C. Each source provides download at a constant rate, but the rates of different sources are not necessarily identical. If the movie was downloaded from sources A and C alone, it would take 4 hours to complete the download. The next day, source B is available, but the other sources are inactive. How long will it take to download the trailer of the movie, a file that is 80 times smaller, from source B alone?