Find the volume, lateral surface area and the total surface area of a cube each of whose edges measures:

(i) 7 m (ii) 5.6 cm (iii) 8 dm 5 cm

(i) We have,

Length of the edge of the cube = a = 7 cm


We know that,


Volume of cube = a3 = 73 = 343 m3


Also,


Lateral surface area of the cube = 4a2


= 4 × 7 × 7


= 196 m2


Total surface area of the cube = 6a2


= 6 × 7 × 7


= 294 m2


(ii) We have,


Length of the edge of the cube = a = 5.6 cm


We know that,


Volume of cube = a3 = (5.6)3 = 175.616 cm3


Also,


Lateral surface area of the cube = 4a2


= 4 × 5.6 × 5.6


= 125.44 cm2


Total surface area of the cube = 6a2


= 6 × 5.6 × 5.6


= 188.16 cm2


(iii) We have,


Length of the edge of the cube = a = 8 dm 5 cm = 85 cm


We know that,


Volume of cube = a3 = 853 = 614125 cm3


Also,


Lateral surface area of the cube = 4a2


= 4 × 85 × 85


= 28900 cm2


Total surface area of the cube = 6a2


= 6 × 85 × 85


= 43350 cm2


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