Arctic explorer

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Arctic explorer

by avenus » Sun Feb 14, 2010 9:40 am
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by outreach » Sun Feb 14, 2010 10:10 am
total surface area= 3*pi*r^2
given
volume=1000
=> (2/3)*pi*r^3=1000
r=10*(3/2*pi)^(1/3)

hence

total surface area=3*pi*10*10*(3/2*pi)^(2/3)

given that painting costs 2.5/foot
=> 2.5*(total surface area)
750*pi*(3/2*pi)^(2/3)

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by ajith » Sun Feb 14, 2010 10:22 am
Volume of the hemisphere = 2/3*pi*r^3 =1000
r^3 = (3000/2pi)
r =(3000/2pi)^1/3


Curved surface area of a hemisphere = 2*pi*r^2
area of the base = pi*r^2

Total area to be painted = 3 *pi*r^2 = 3*pi*(3000/2pi)^2/3
Total cost = 2.5* 3*pi*(3000/2pi)^2/3 =7.5*100pi*(3/2pi)^2/3 =750*pi*(3/2pi)^2/3
Always borrow money from a pessimist, he doesn't expect to be paid back.