###Human: The Donaldsons pay $15 per hour for babysitting. The Merck family pays $18 per hour and the Hille family pays $20 per hour for babysitting. Layla babysat for the Donaldsons for 7 hours, the Merck family for 6 hours and the Hille family for 3 hours. How many dollars did Layla earn babysitting?, ### Assistant: Donaldsons pay $15/hour = 15*7 = $105.
The Mercks pay $18/hour = 18*6 = $108.
The Hilles pay $20/hour = 20*3 = 60.
The total amount Layla earned is 105 + 108 + 60 = 273.
Layla earned $273 for babysitting. 
 So the answer is :  273