# Math

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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.

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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

check:
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.

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oops. typo that's
3(1±√481)

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thanks!

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dhek bhai phely minutes ko convert kro phir jo answer aye us ko 240se add kr k equation se agey solve krlo

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galat galat ammar galat

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kk thanks