Question

Three cubes of metal with edges 7.5cm, 6cm and 4.5cm respectively are melted to form a new cube. Find thei) Volume of the new cube formed
ii) Edge of the new cube formed.
iii) Total surface area of the new cube formed

Answer 1

Answer:

• To solve this problem :- we should find the volume and add it.

Volume of cube 1 ;

(7.5)^3 = 421.875 cm^3

Volume of cube 2 ;

(6)^3 = 216 cm^3

Volume of cube 3 ;

(4.5)^3 = 91.125

i) Volume of new cube :-

➡ 216 + 91.125 + 421.875 = 729.

ii) Edge of the new cube :-

a^3 = 729

a = 3√729

a = 9.

Edge of the cube is 9 cm.

iii) Total surface area of the new cube :-

6a^2 = total surface area of cube.

a = 9.

6 (9^2) = 486 cm^2