In a rectangular park that is 60 meters by 91 meters, a dog began in the northwest corner and ran south along the length of the park. Then the dog ran east along the width to the southeast corner. Finally, the dog ran back to the northwest corner. How far did the dog run?

The correct answer is 260

Let the rectangular park be as shown in the figure.

As per Pythagoras Theorem,

$a^2 + b^2 = c^2$

Hence $c^2$ = $60^2 + 91^2$ ⇒ $c = 109$

The dog ran from point A to point B to point C and then back to point A.

Hence the distance ran = $a + b + c$ = $60 + 91 + 109$ = $260$ meters