Answer:
Fraction of the scouts are square dancing is 
 .
. 
Explanation:
Each pair is one Girl Scout and one Boy Scout. 
So, to the final fraction ( of the pairs) we are going to get 1/2 from the fraction of girls and 1/2 from the fraction of boys. 
Girls= 

Boys= 

To get the fraction of the scouts that are square dancing, we have to add the fraction of girls , with the fraction of boys. 
=

=

=

=

This means that from 30 scouts , 19 are dancing.