x/ 10- 1/ 15 = x/ 18
Solution, x= 1.5
Then the uphill time is1.5/10 = 0.15 hours =9 minutes.
So leveling the road takes 29-9=20 minutes = 1/3 hours.
The length of flat road is 15 * 1/3 = 5km.
So the distance from A to B is 1.5+5 = 6.5km.
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