Given : Length of cuboidal box l= 60 cm
Breadth of cuboidal box b = 40 cm
Height of cuboidal box h= 50 cm
Total surface area of cuboidal box = 2(lb+bh+hl)
=2(60×40+40×50+50×60)=2(2400+2000+3000)=2×7400=14800 cm2
(b) Given: Length of cuboidal box l = 50 cm
Breadth of cuboidal box b = 50 cm
Height of cuboidal box h = 50 cm
Total surface area of cuboidal box = 2(lb+bh+hl)
=2(50×50+50×50+50×50)=2(2500+2500+2500)=2×7500=15000 cm2
Hence, cuboidal box (a) requires the lesser amount of material to make, since surface area of box a is less than that of box (b).