<PRE><B>Question 269058</B>
Carel left the airport and drove toward the capital at an average speed of 52km/h. Some time later Mei left driving in the same direction but at am average speed of 65km/h. After driving for four hours Mei caught up with Carel. Find the number of hours Carel drove before Mei caught up.

let Carel leave x hours before Mei.
Carel drives at 52kmph

------------(52x ) ------------(260-52x)

_________________:_________________________: Carel in x+4 hours

------(x hours)----------------(4 hours)


----------------------260 kms-----------------: 
:---------------------------------------------:  Mei in 4 hours
                        
Distance traveled by Carel before Mei starts is 52*x

Mei caught up with Carel after 4 hours .
Which means she drove for 260 miles. They meet at 260 km distance.

So distance travel by Carel after Mei started = 260 - 52x

Total distance traveled by carel / the time she drove = her speed.

52x+260-52x / x+4= 52

260= 52*(x+4)

260= 52x+208

260-208=52x

52=52x

x=1  hour.

So Carel drove for 5 hours when Mei caught up with her.


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