Question 1207357
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in a certain community with a population of 45000 it is estimated that each person needa 
12 liter of water each day the community has a centralized reservoir which is cylindrical 
with a radius of 7m and height 20m if the reservoir is half fulled how long to yhe nearest day 
will the water last
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The volume of the cylindrical reservoir is

    V = {{{pi*r^2*h}}} = {{{(22/7)*7^2*20}}} = 3080 m^3,  or  3,080,000 liters.


The volume of the water is half the volume of the cylindrical reservoir,
i.e.  3080000/2 = 1540000  liters.


The number of days is  {{{1540000/(45000*12)}}} = {{{1540/(45*12)}}} = 2.85.


The nearest integer number of days is 3, but the amount of the water is not enough for 3 full days
at the given normative of 12 liters per person per day.
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