After travelling 35 km North, then 12 km East, then 20 km South, then 4 km West, how far is the traveller from the starting point by the shortest route?

Important Notes

• Draw a north arrow before solving and take East as positive x, West as negative x, North as positive y, and South as negative y. |
• Combine opposite movements before calculating distance: cancel East with West and North with South. |
• Decide the final direction from the signs of the remaining horizontal and vertical displacements. For example, positive x and negative y indicate South-East. |