Question

a particles move 3m north, then 4m east and finally 6m south. calculate the total distance and the displacement of the particles

Answer 1

Distance covered by the particle = 3+4+6 = 13 m

Displacement = $\sqrt{3^{2}+4^{2} }$
                         = $\sqrt{25}$
                         = 5

Answer 2

Total distance: 3m+4m+6m=13m
Total displacement =shortest distance from initial positon to final position.
according to the question you can plot the diagram as here attached file.
Usign pythagoras theorem.
you can find the displacement as:3²+3²=(displacement)²
displacement=√9+9
                     =√18