# The Boundary Of A Square Field Of Area

A motorist travels along the boundary of a square field of area 1476225 m square , at 36 km/hr. he returns to starting point in

- 8 min, 8 sec
- 6 min, 8 sec
- 8 min, 6 sec
- 6 min, 6 sec

**Answer: (3) 8 min 6 sec**

**Explanation:-**

The area of square field = 1476225 m^{2}

**Formula-**** The area of square field = Side x Side**

Then, Side of square field = (1476225)^{1/2}

= 1215 m

**Formula-**** The perimeter of square field = 4 x side**

then, the perimeter of field = 4 x 1215

= 4860 m

4860 m = 4860/1000 km

= 4.860 km

Now, the speed of the motorist travels = 36 km/h

Time taken to covered distance by the motorist = 4.860/36

= 0.135 h

1 hr = 60 x 60 sec

Therefore, 0.135 h = 0.135 x 3600 sec

= 486 sec

1 sec = 1/60 min

Therefore, 486 sec = 486/60

= 8 min 6 sec.

Hence, the answer is (3) 8 min 6 sec.