The interstate on-ramp is 5.5 km west of your home, and on leaving for your friend's house, you are only able to go an average of 38 km per hour between your home and the on-ramp. You wait in traffic for 2 minutes at the on-ramp before continuing to your friend's house. Your friend's house is 15 km south of the on-ramp. If you want to have traveled at an average velocity of 42 km/hr for the whole trip, how fast do you need to drive south on the interstate highway?

The correct answer is 48.38 km/hr. I need to see the working