It takes Engineer Kweku three hours to drive to his brother’s house at an average speed of 50 miles per hour. If He takes the same route home, but his average speed is 60 miles per hour, what is the time, in hours, that it takes him to drive home?

  2.5 hours

Step-by-step explanation:

The product of speed and time is distance. If the distance is the same, then time is inversely proportional to speed. At 60/50 = 6/5 times the speed, the return trip will take 5/6 times the time:

  (5/6)(3 hours) = 2.5 hours . . . time for return trip

answer: there are 453.592 grams in a pound.