Answer:
Fraction of the scouts are square dancing is
.
Step-by-step 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.
The line goes 3 right for every 1 down, so the gradient is -1/3
The y-intercept is +4, so the equation is actually y=-1/3x+4, so Chris is wrong.
First, factor out h so the equation can be h(b+r)=25 then divide by b+r so h= 25/b+r