Surface area cube

Question

A cube of lead of sides 8cm is cut into cubes of sides 2cm.

Find the surface area of the large cube and the total surface area of the small cubes to determine by how much the surface area has been increased.

Answer 1

Surface Area of LARGE 8cm CUBE = (6 SIDES) (AREA OF ONE SIDE)=(6)(8x8)=(6)(64)=384 SQ CM

Surface Area of SMALL 2cm CUBES= (NUMBER OF 2CM CUBES) (6 SIDES) (AREA OF EACH SIDE)

...........................................................= (4 x 4 x 4) (6) (2 x 2)

...........................................................= (64) (6) (4)

...........................................................= (64) (24)

...........................................................= 1,536 SQ CM

SURFACE AREA INCREASED BY 1,536 - 384 = 1,152 SQ CM

ANSWER: 1,152 SQ CM

Hope this was helpful LEO.