



 
Hi Ekanem, The important fact in this problem is that \[\mbox{rate} = \frac{\mbox{ distance}}{\mbox{ time}}.\] First for the entire trip the distance is 196 km and the time is 2 hours so the average rate is \[\frac{196}{2} = 98 \mbox{ km per hour.}\] Since he only averages 40 km per hour for the first 15 km he needs to average more than 98 km per hour to make it in 2 hours. Now let's solve the problem. For the first 15 km use the fact that \[\mbox{rate} = \frac{\mbox{ distance}}{\mbox{ time}}\] to calculate the time it takes. If he is to complete the trip in 2 hours how much time does he have left? For the second part of the trip use the fact that \[\mbox{rate} = \frac{\mbox{ distance}}{\mbox{ time}}\] to calculate the average speed required. Penny  


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