DS: Gold covered sphere

Question

see attached

jainvik7 · Answer

Volume of the inner sphere ---> 4/3 * pi * 5^3

Volume of the outer sphere (Sphere with gold ) ---> 4/3 * pi * (5 + 1)^3 = 4/3 * pi * 6^3

Hence the volume of gold -- >

Volume of the outer sphere - Volume of the inner sphere = 

4/3 * pi * 6^3 - 4/3 * pi * 5^3
= 4/3 * pi (6^3 - 5^3) = 4/3 * pi * (216 - 125) = 4/3 * pi * 91 = 364 *pi/3 = k*pi/3

Hence k = 364

MA · Answer

(k pi)/3 + (4 pi r^3)/3 = (4 pi (r+1)^3)/3
pi  /3 = (4 pi (5+1)^3)/3
solving for k = 386.

hawk · Answer

(4*pi*6^3)/3 - 4*pi*5^3)/3 = k*pi/3

4*6^3 - 4*5^3 = k

k = 364

vij101 · Answer

4/3*Pi* (5+1)^3 = 4/3*Pi*5^3 + K*Pi/3

solve for K 
Ans K= 364....C

freetheking · Answer

V= 4/3*pi*r^3
 = 4/3*pi*(6^3-5^3) = 4/3*pi*(91) = 364*pi/3

k*pi/3 = 364*pi/3

K = 364.

jaynayak · Answer

Volume of original sphere = 4/3 pi * 5^3

Volume of gold plated sphere = 4/3 pi * 6^3

Volume of gold plating = Kpi/3

4/3 *pi ( 6^3 - 5^3) = Kpi/3

4/3 Pi * 91 = K pi /3

K = 91*4 = 364

gmatmathguru · Answer

Hi Kevincan,

I would like to post a topic that has a word document; sort of like your post here. can you show me how to do it?

is this done as a html? Can you send me a template or stub I can use.

thanks,

-mathguru

haas_mba07 · Answer

Answer: C. 364 

Vol of inner sphere : 4/3 * pi * 5x5x5 

Vol of outer sphere : 4/3 * pi * 6x6x6

Volume of gold = 4/3 * pi * (216 - 125) = k/3 * pi 

Solving k = 364.

ps_dahiya · Answer

4PI(6^3 - 5^3)/3 = k PI/3
k = 4 * (216-125) = 4 * 91 = 364

kevincan · Answer

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DS: Gold covered sphere

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