Question

A man goes $12$ miles due east and then $9$ miles due north. Calculate the distance travelled, if he takes the theoretically shortest path.

• A. $3$
• B. $\sqrt{63}$
• C. $15$
• D. $21$
• E. $225$

Answer 1

Answer: (C)

$15$

It will form a right angled triangle where one side is $12$ miles and the other sides is $9$ miles.

Now we know that the sum of two sides is greater the the third side.

Hence he travels $21$ miles, but if he takes the shortest path then he will walk along the hypotenuse.

The length of the hypotenuse will be

$=\sqrt{{12}^2+9^2}=\sqrt{144+81}=\sqrt{225}=15$