On the first part of a 350kilometer trip a salesperson trave

On the first part of a 350-kilometer trip, a salesperson travels 2 hours and 15 minutes at an average speed of 100 kilometers per hour. The salesperson needs to arrive at the destination in another hour and 20 minutes. Find the average speed required for the remainder of the trip.

Solution

Applying the distance formula: d = rt
.
distance traveled during the first part:
2.25(100) = 225 km
.
remainder of trip:
350 - 225 = 125 km left to go
.
average speed he needs to travel:
4/3 is equivalent to 1 hr 20 minutes
125/(4/3) = (3/4)(125) = 93.75 kilometers per hour