There are 4/7 boys, so there are 3/7 girls.
Let the total number of children be x.
4/7x = 8
1/7x = 8 ÷ 4
1/7x = 2
3/7x = 2 x 3
3/7x = 6
There are 6 girls.
Do 50 multiplied by x = 8. Solve for x.
It would give you .16 which is 16%.
Approx. 5 miles I would say give or take the 1/2 mile shortcut by taking a straight path back to the house. I don't know if you need an exact distance but I hope this helps.