A person starts from a point A and travels 3 km east - wards to B and then turns left and travels thrice that distance to reach C. He again turns left and travels five times the distance he covered between A and B and reaches his destination D. The shortest distance between the starting point and the destination is?

Draw the figure of movement with the help of given below direction graph.
A person starts from a point A and travels 3 km East - Wards to B. Then he turns left and travels 9 km to reach C.
He again turns left and travels 15 km and reaches his destination D.
The movements of the person are as shown in Figure
Clearly, AB = 3 km, BC = 3AB = (3 × 3) km = 9 km, CD = 5AB = (5 × 3) km = 15 km,
Draw AE ? CD.
Then, CE = AB = 3 km
AE = BC = 9 km
DE = (CD ? CE) = (15 ? 3) km = 12 km.
In triangle AED, AD² = AE² + DE²
or AD² = 9² + 12²
or AD² = 81+ 144
or AD² = 225
or AD² = 15²
AD = 15
Required distance = AD = 15 km