The GMAT Sample Math question is from the topic Mensuration.
The area of a square field is 24200 sq m. How long will a lady take to cross the field diagonally at the rate of 6.6 km/hr?
A. 3 minutes
B. 0.04 hours
C. 2 minutes
D. 2.4 minutes
E. 2 minutes 40 seconds
The correct choice is (C) and the correct answer is 2 minutes.
Let 'a' meters be the length of a side of the square field.
Therefore, its area = a2
square meters. --- (1)
We know that the length of the diagonal 'd' of a square whose side is 'a' meters =
a --- (2)
From (1) and (2), we can deduce that the square of the diagonal = d2
Or d =
The time taken to cross a length of 220 meters while traveling at 6.6 kmph is given by
(converting 1 km = 1000 meters and 1 hour = 60 minutes).
= 2 minutes