math
posted by Charles .
A pool of water with surface area of 0.6 hectares has a uniform depth of 3 metres.A pipe drains water in the pool at the rate of 200 litres per second.How much hours does it take to empty the pool?

area * depth = volume
time = volume/volume rate
1 hectare = 1000 m^2
1 liter = 10^3 m^3
1 hr = 3600 seconds
so
time in hours = .6hec(10^3m^2/hec)*3m/(200 L/s *1m^3/10^3 L * 3.6 *10^3 s/h)
= .6*3/(200*3.6) *10^3
= 0.5 hr
check my arithmetic
200 l/s * t = 
0.6*10000
6000m 3*200=600