Easy
Abi walks 10 km towards North. From there he walks 6 km towards South. Then he walks 3 km towards East. In which direction is Abi now with reference to the starting point?
Step 1: As found above, Abi's final position is 4 km north and 3 km east of the starting point. Step 2: Since both displacements are positive (north and east), the final position lies in the North-East direction from the start. So Abi is to the North-East of his starting point.
Re-check your working by substituting the answer back into the original question.