###Human: Trevor needs to go downtown for a restaurant date. An Uber ride downtown costs $3 more than a Lyft ride. A Lyft ride costs $4 more than a taxi ride. The Uber ride costs $22. If Trevor takes a taxi downtown and tips the taxi driver 20% of the original cost of the ride, what is the total cost of the ride downtown?, ### Assistant: The cost of the Lyft ride is $22 - $3 = $19
The original cost of the taxi ride is $19 - $4 = $15
Trevor tips the taxi driver $15 * 0.20 = $3
The total cost of the ride downtown is $15 + $3 = $18 
 So the answer is :  18