About how accurately must a 70 meter high cylindrical tank's exterior diameter be measured to calculate the amount of paint it will take to paint the side of the tank to within 5% of the true amount? Express your answer as a percentage of the outer diameter:

Question

anonymous · Answer

Do you understand the answer given on Yahoo? I don't at all :/

mrdoe · Answer

so essentially you want the total error propagated though the volume equation to equal 1%

amistre64 · Answer

how do we calculate the surface area of a cylindar?

amistre64 · Answer

circumference times height

2pi r h = SA

amistre64 · Answer

to be within 5% of SA we have

2pi r h = SA(1.05)

or

2pi r h = SA(.95)

amistre64 · Answer

dividing we have:  h/(1.05)  or h/(.95),  and h=70

zephyr141 · Answer

where did the r come from?

amistre64 · Answer

the base circles radius

amistre64 · Answer

circumference of a circle is 2pi r,  and we have h of them for the lateral area

amistre64 · Answer

About how accurately must a 70 meter high cylindrical tank's exterior diameter 

thought we were doing height

amistre64 · Answer

change h to d and we get the same concept

amistre64 · Answer

is 70 the height of the side of a tank, or is that the diameter of the tank?

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