When you normally drive the freeway between Sacramento and San Francisco at an a
ID: 1588634 • Letter: W
Question
When you normally drive the freeway between Sacramento and San Francisco at an average speed of 100 km/hr (62 mi/h), the trip takes 1.00 hr and 24 min. On a Friday afternoon, however, heavy traffic slows you down to an average of 75 km/hr (47 mi/h) for the same distance.Question: How much longer does the trip take on Friday than on other days?
(Express your answer in minutes to the nearest integer.) When you normally drive the freeway between Sacramento and San Francisco at an average speed of 100 km/hr (62 mi/h), the trip takes 1.00 hr and 24 min. On a Friday afternoon, however, heavy traffic slows you down to an average of 75 km/hr (47 mi/h) for the same distance.
Question: How much longer does the trip take on Friday than on other days?
(Express your answer in minutes to the nearest integer.)
Question: How much longer does the trip take on Friday than on other days?
(Express your answer in minutes to the nearest integer.)
Explanation / Answer
how much longer does the trip take?
let the distance travelled be x km
speed = total distance / time
=> total distance = x = speed x time (in either case)
=> 100[1 + (24/60)] = 75t
=> t = (100/75)[100*0.4/75] =1.86 ~ 1 hr 52 minutes
Ans: it takes ~ 28 min more