Posted by Elizabeth on Monday, December 10, 2012 at 10:16am.
A motorist makes a journey of 240 km from Singapore to Malacca to visit his inlaws at an average speed of x kilometers.
On his return journey, his average speed is reduced by 6km/hour due to traffic.
If the return journey takes 20 minutes longer, form an equation with x and solve it to find the average speed of each journey, giving your answer correct to two decimal places.
So: 240/x is the number of hours taken for the first journey.
240/x-6 is the time it takes for the return journey.
What do I do next? Please help!
Math - Steve, Monday, December 10, 2012 at 10:31am
and you know that the return journey takes 1/3 hour longer than the one going.
240/x + 1/3 = 240/(x-6)
x = 3(1+±481) = 68.80
240/62.80 = 3.82
240/68.80 = 3.49 = 3.82
difference: .33 hr = 20 min
you got the setup right, but didn't take that final step. Be sure to analyze everything they tell you, and the solution will emerge.
Math - Steve, Monday, December 10, 2012 at 10:32am
oops. typo that's
Math - Elizabeth, Monday, December 10, 2012 at 10:48am
Math - ammar, Sunday, December 7, 2014 at 3:37am
dhek bhai phely minutes ko convert kro phir jo answer aye us ko 240se add kr k equation se agey solve krlo
Math - titu mir, Sunday, December 7, 2014 at 3:39am
galat galat ammar galat
Math - Anonymous, Monday, May 2, 2016 at 6:11am
Answer This Question
More Related Questions
- maths - 1. A train was travelling at an average speed of 80km/h. If the train ...
- math-calculus - a plane flew from red deer to winnipeg, flying distance of 1260 ...
- Math - Kate cycles the first 350 km of a 470 km journey at a certain average ...
- Mathematics - A motorist do does the first part of his journey at an average ...
- Mathematics - For the first 1 1/2 hours of a 91km journey the average speed was ...
- math - A motorist does the first part of the journey at an average speed of 54 ...
- Math - Mr. Njinga cycled a distance of 42km from his village. On his return ...
- math - to save fuel on the 240 km trip to the cottage, the Nakamura family ...
- math...? - to save fuel on the 240 km trip to the cottage, the Nakamura family ...
- Maths-Proportions - 1) An aircraft flying at 500 km/h completes a journey in 8.4...