After walking 3 miles in opposite directions, A and B are 3 miles apart from each other.

When A turns right and walks 4 miles, and B turns left and walks 3 miles, they essentially form a right-angled triangle.

Let's call the point where A turns right as point C and the point where B turns left as point D.

Now, we can use Pythagoras theorem to find the distance from each of them to the starting point.

The distance AC from A's starting point = √(3^2 + 4^2) = √(9 + 16) = √25 = 5 miles.

The distance BD from B's starting point = √(3^2 + 3^2) = √(9 + 9) = √18 ≈ 4.24 miles.

So, A is 5 miles away from the starting point, and B is approximately 4.24 miles away from the starting point.