On a training ride, Laura averages speeds of 12 km/h for 5 minutes, then 15 km/h for 10 minutes and finally 18 km/h for 15 minutes.
What was her average speed over the whole ride?
Select one option, then click Submit.
13 \text{ km/h}
14 \text{ km/h}
15 \text{ km/h}
16 \text{ km/h}
17 \text{ km/h}
Select an option, then submit.
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