The area of a square field is 1600 km2. How long will it take for a horse to run around at the speed of 16 km/h ? Choose the correct option:
A) 12 h
B) 10 h
C) 8 h
D) 6 h
E) None of these
Explanation Area of field =1600 km2. Then, each side of field = √1600=40km Distance covered by the horse = Perimeter of square field = 40 × 4 = 160 km ∴ Time taken by horse = distances/peed=160/16= 
<gadget id="calculator">160/16</gadget>
<output>10</output>
10h Answer 10 h
<result>B</result>
The area of a square field is 1600 km2. How long will it take for a horse to run around at the speed of 16 km/h ?