Quant/Math - CAT 2008
Question 4 the day: Mensuration -
March 22, 2004
The question for the day 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?
(1) |
3 minutes
|
|
|
(2) |
2 minutes
|
(3) |
2.4 minutes
|
|
|
(4) |
2 minutes 40 seconds
|
Correct choice - (2) Correct Answer -(2 minutes)
Solution:
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
=
21/2
a �-- (2)
From (1) and (2), we can deduce that the square of the diagonal = d2
= 2a2
Or d =
(2*area)1/2 = (2*24300)1/2 = 484001/2 =220meters.
The time taken to cross a length of 220 meters while traveling at 6.6 kmph is
given by
220 meters / 6.6kmph = 220*60 /
6.6*1000(converting 1 km = 1000 meters and 1 hour = 60 minutes).
= 2 minutes
|