Four sisters and three brothers.
Super Simple Trick to Solve It:
- Let’s assume there are X sisters and Y brothers.
- Each girl has (Y) brothers and (X – 1) sisters. → ✅ X – 1 = Y
- Each boy has (X) sisters and (Y – 1) brothers → ✅ (Y – 1) = X / 2
- Solving gives X = 4, Y = 3
