please help me

Question

Adam's father stars off to drop adam at his school 9.2 km away driving at 30 km/hr .After 4 minutes ,jatin tells his fther that he has to reach schol in another 10 minutes.At what speed must Adam's father drive to reach the schol on time

 

Answer 1

Distance for the first 4 minutes  + Distance for the remaining 10 minutes = 9.2 km

 

   4 min = 1/15 hr   10 min = 1/6 hr

 

Distance = (Rate)(Time)

 

So, (20 km/hr)(1/15 hr) + (x km/hr)(1/6 hr)) = 9.2 km

 

Multiply by the LCD, 90, to obtain 120 + 15x = 828

 

                                                       15x = 708

 

                                                          x = 47.2 km/hr