2 minute is taken to travel the diagonal of square field at 3km/hour.calculate the area of field?  Pick one: A) 25 are B) 30 are C) 50 are D) 60 are E) 45 are

Rationale: speed of man = [ 3 * 5 / 18 ] m / sec . = 5 / 6 m / sec . , distance travel in 2 minute = { 5 / 6 * 2 * 60 } m . = 100 m . diagonal of square field = 100 m area of field = 1 / 2 * diagonal ^ 2 = [ 1 / 2 * 100 * 100 ] sq . m = 5000 sq . m = 5000 / 100 = 50 are ( 1 are = 100 sq . m ) answer c
Answer: C