Question

a cube has been formed by melting three cubes of metal with age is 3 cm 4 cm and 5 cm .Find the CSA of the new cube

Answer 1

Answer:

edges of cubes are = 3cm, 4cm, 5cm

vol. of the three cubes are = 3×3×3 = 27cm^3 , 4×4×4 = 64cm^3 and 5×5×5= 125cm^3

ATQ, vol. of bigger cube = sum of the vol. of the three cubes

vol. of bigger cube = 27 + 64+ 125 = 216cm^3

then the edge of cube = 6cm

CSA of bigger (new) cube = 4 × edge of cube

                                           = 4 × 6 = 24cm^2

hope this answer is correct