SOLUTION: Raymond cycled from Tampines to Jurong at an average speed of 30 km/h. For the first 20% of the journey, he travelled at only 20 km/h and reached Bedok where he stopped for 1/3 of

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Question 979940: Raymond cycled from Tampines to Jurong at an average speed of 30 km/h. For the first 20% of the journey, he travelled at only 20 km/h and reached Bedok where he stopped for 1/3 of an hour. After that, he travelled 36 km to reach Jurong. How long did he take to travel the 36 km?
thanksss this one is so hard
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +d+ = the total distance of the journey in km
From the given data:
+.2d+%2B+36+=+d+
+.8d+=+36+
+d+=+36%2F.8+
+d+=+45+ km
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+.2d+=+.2%2A45+
+.2d+=+9+ km
For the 1st 20% of trip:
+9+=+20t+
+t+=+9%2F20+
+t+=+27%2F60+ hrs
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For the entire trip:
+45+=+30%2At+
+t+=+90%2F60+ hrs
This is just the time spent cycling
---------------------------------
+90%2F60+-+27%2F60+=+63%2F60+
The time to travel the last 36 km is:
63/60 hrs = 1 hr 3 min
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By my reasoning, the legth of time he
spends stopped is irrelevant. I could
be wrong on that -you should get
another opinion.