1. Good post? |

## cube problem

A 4 cm cube is cut into 1 cm cubes. What is the percentage increase in the surface area after such cutting?
4%, 300%,75%,400%,5%

2. Good post? |
One 4cm*4cm*4cm cube = 4*4*4 1cm*1cm*1cm cubes

Surface Area of 4 cc cube = 6*4*4
Surface Area of 1 cc cube = 6*1*1
Total Surface Area of the 64 1cc cubes = 64*6

&#37; increase = 100*(64*6-6*4*4)/6*4*4
i.e, 300%

3. Good post? |
great krovvidy....there is a little variant to this problem

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A 5 cm cube is cut into as many 1 cm cubes as possible. What is the ratio of the surface area of the larger cube to that of the sum of the surface areas of the smaller cubes?
1: 6
1: 5
1: 25
1: 125
1:435
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4. Good post? |
6.5.5/ (125.(6.1.1)) = 25/125....1:5.
I only posted this question to reveal the twist

5. Good post? |
answer to this question is 300&#37;
surface area of cube = 6a2
hence 6*4*4 = 96
no. of cubes now = 64
surface area 64*6 = 384 increase = 288
% increase = 300%

6. Good post? |
answer to tyro question is 5

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