question_answer

A man walks 1 km towards East and then he turns to South and walks 5 km. Again he turns to East and walks 2 km, after this he turns to North and walks 9 km. Now, how far is he from his starting point?

A) 3 km

B) 4 km

C) 5 km

D) 7 km

Correct Answer: C

Solution :

Explanation: The movements of the man are as shown in figure. (A to B, B to C, C to D, D to E). Clearly, \[DF=BC=5\text{ }km\] \[EF=\left( DE-DF \right)=\left( 9-5 \right)km=4\text{ }km.\] \[BF=CD=2\text{ }km\] \[AF=AB+BF=AB+CD=\left( 1+2 \right)km=3\text{ }km\]Man?s distance from starting point A \[=AE=\,\,\sqrt{A{{F}^{2}}+E{{F}^{2}}}=\,\,\sqrt{{{3}^{2}}+{{4}^{2}}}\] \[=\,\,\sqrt{25}=5\,km.\]