question_answer

Kunal walks 10km towards North. From there the walks 6 km towards South. Then, he walks 3 km towards East. How far and in which direction is he with reference to his starting point?

A) 5 km West

B) 7 km West

C) 7 km East

D) 5 km North-east

E) None of these

Correct Answer: D

Solution :

Explanation Option (d) is correct. Clearly, Kunal moves from A 10 km north-wards up to B, then moves 6 km southwards up to C, turns towards East and walks 3 km up to D. Then, \[AC=\left( AB-BC \right)=\left( 10-6 \right)=4\text{ }km;\text{ }CD=3\text{ }km.\] So, Kunal's distance from starting point \[A=AD=\sqrt{A{{C}^{2}}+C{{D}^{2}}}=\sqrt{{{4}^{2}}+{{3}^{2}}}=5\,km\] Also, D is to the North-East of A. Hence, the answer is (D)