posted by Juliana
Bob is going from his house to his uncle Sam's house in another state. He started running. After a while he switches to a bicycle. After a while he switches to a truck. After a while he switches to a sports car. After a while he switches to a helicopter. In each segment he travels twice as fast and for twice the time period of the previous mode of transportation. His total trip's take two hours and four minutes. If he ran at a speed of 15 ft per second. How far is uncle Sam's home.
Let x be the time running, in minutes.
Then 2x, 4x, 8x, and 16x are the times on the bike, truck, car, and helicopter, respectively, in minutes.
Total time = 2 hours and 4 minutes = 124 minutes
x + 2x + 4x + 8x + 16x = 124
x = 4 minutes
4 minutes = 240 seconds
distance to uncle sam's home:
= (15)(240) + (30)(480) + (60)(960) + (120)(1920) + (240)(3840) feet