Manoj walks 12 metres towards north. Then turns right and walk another 12 metres. Then turn right and walks for 7 metres to reach college R. He again turns to his right and walks for 12 metres. What is the straight line distance (in metres) between the starting point and college R?

Let's trace Manoj's movement step-by-step from the starting point O(0,0):
Manoj walks 12 m North to point A(0,12).

He turns right (East) and walks 12 m to point B(12,12).

He turns right (South) and walks 7 m to reach College R. The coordinates of R become (12,12−7)=(12,5).

We need to find the straight-line distance between the starting point O(0,0) and college R(12,5).
Using the distance formula:

Distance=
(12−0)
2
+(5−0)
2


​

Distance=
12
2
+5
2


​
=
144+25

​
=
169

​
=13 metres