1. In his text he mixed the number of boys and girls.
The problem talks about 3 girls and 5 boys.
But in his logic it does not affect his results.
2. The second notice is more serious.
I will use another logic and will get another answer.
Since the team of boys and girls is arranged in a circle, we can think that the girls go first ("women first")
and we arrange and count our circular permutations starting from the girls.
We can start counting (arranging) from any of the 3 girls, arranging them in 3! = 6 ways.
Then we arrange 5 boys by 5! = 120 ways (120 permutations for 5 objects).
That's all. In all we have 6*120 = 720 circular arrangements.
There is no need to divide 720 by 8, because we just accounted for the circular symmetry, when started our arrangements from the girls.
So, my answer is 6*120 = 720 ways/(circular arrangements).
