A 4 cm cube is cut into 1cm cubes. What is the percentage increase in the surface area after such cutting?
Initial surface area of the cube = 6$$(side)^2$$Â
= 6$$(4)^2$$Â
= 96$$cm^2$$
No. of new cubes = $$\ \ \frac{\ Volume\ of\ older\ cube}{Volume\ of\ 1\ new\ cube}$$
=$$\ \ \frac{\ 4\times\ 4\times\ 4}{1\times\ 1\times\ 1}$$
=64 cubesÂ
Newer surface area of 64 cubes = 64*6$$(1)^2$$ = 384$$cm^2$$
Percentage increase in surface area = $$\ \ \frac{384-96}{96}$$ *100
=$$\ \ \frac{28800}{96}$$
 = 300%
B is the correct answer
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