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kyla_14
Jul 5, 2009, 11:12 AM
How can I answer this?
This is d probLem :
U nOrmally drive on the freeway between San Diego and LOs angeles at an average speed of 105 km/h (65 miles/h) and the trip takes 2h and 20min. On Friday afternoon, however heavy trafficslows you down ang you drive the same distance at an average speed of only 70 km/h (43miles/h). How much lOnger dOes the trip take?

HOpe you can heLp me.. show the sOLution.. tnx..

Unknown008
Jul 5, 2009, 11:20 AM
Work out the distance by the formula

Speed = \frac{Distance}{Time}

Then, with that distance, find the time taken to travel that distance with the new speed.

Compared the two values for time you have got, and Voilą! :)

Perito
Jul 5, 2009, 11:24 AM
How can I answer this?
This is the problem:
One normally drives on the freeway between San Diego and Los Angeles at an average speed of 105 km/h (65 miles/h) and the trip takes 2h and 20min. On Friday afternoon, however, heavy traffic slows you down and you drive the same distance at an average speed of only 70 km/h (43miles/h). How much longer does the trip take?


Distance = Rate x Time.

Rate is also known as the velocity or the speed.

1. SD to LA; Rate = 104 km/h; Time = 2.333 hours (2 1/3 hours). Solve for Distance.

2. SD to LA on Friday afternoon. Rate = 70 km/h. Distance is the same as in #1. Solve for Time.

Make sure your units are always the same. For example, if you used rate in km/h the distance will end up in km. If you then used the rate in mph your distance would have to be in miles and not kilometers.