(10+ points)Please help me.My sister really need this now.Please answer this seriously,don't answer if you don't know the answer and solution.please be serious,thank you in advance.

Shiela wanted to go to her friend's house which is 24 km from her house.If she drives her motorcycle with a speed of 60 kph,she will be there in 24 minutes. If she makes her speed slower to 40 kph,how long would Shiela take to reach her friend's house?

Answer:

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