###Human: There are 11 boys and 13 girls in a class. If 1 boy is added to the class, what percentage of the class are girls?, ### Assistant: There are a total of 11 + 1 = 12 boys in the class.
Hence, there are a total of 12 boys + 13 girls = 25 students in a class.
So 13/25 x 100% = 52% of the class are girls. 
 So the answer is :  52