Alok walks from point P to point Q, which is 6 km away, then turns right and walks for 12 km to point R, again turns right and goes 11 km to point S. What is the distance between points P and S?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → 13 km
The first direction is not given, so take P to Q as North; any other start only turns the whole path round and gives the same distance. Each turn is taken from the direction Alok is facing:
Facing North, a right turn is East: Q to R is 12 km East
Facing East, a right turn is South: R to S is 11 km South
S is 12 km East of P and \(11-6=5\) km South of it. These two distances are the arms of a right triangle with PS as the hypotenuse:
\(PS=\sqrt{12^2+5^2}=\sqrt{169}=13\) km