Question 177627
Although this appears to be a travel word problem, it's actually a rate-of-work problem where the complete job is travelling from one end of town to the other.

Let x=amount of time it takes Dolly alone to pedal from one end of town to the other

So Dolly pedals at the rate of 1/x of the distance from one end of the town to the other per hour 

Kenny pedals at the rate of 1/3 of the distance from one end of town to the other per hour

Dolly & Kenny together pedals at the rate of 1/2 of the distance from one end of town to the other per hour

So our equation to solve is:
1/3 + 1/x = 1/2  multiply each term by 6x
2x+6=3x subtract 2x from each side
3x-2x=2x-2x+6 or
x=6 hours  time for dolly to travel alone from one end of town to the other

CK
1/3 +1/6 = 1/2
2/6+1/6=1/2
1/2=1/2


Does this help??? ----------ptaylor