Question

A cubical box has each edge 10 cm another cuboidal box is 12.5 cm long 10 cm wide and 8 cm high.
(i)which box has grearer lsa and by how much
(ii)which box has smaller tsa and by how much

Answer 1

1)Lsa of cubical Box = 4a2
= 4 × 10 × 10
= 400cm2
LSA of cuboidal box= 2h(l+b)
=2×8(12.5+10)
=16×22.5
=360cm2

So cubical box has greater lsa by 40cm2

2)Tsa of cubical box= 6a2
=6× 10×10
=600cm2

Tsa of cuboidal box = 2 (lb + bh + lh)
= 2( 125 + 80 + 100)
= 2× 305
=610cm2

so cuboidal box TSA is more by 10cm2

Answer 2

Lsa of cube - 4l²
4(10)²--400cm²
Lsa of cuboid-- 2(l+b) h
2(12.5+10)8
2(22.5)8
45*8
360cm²
So the lsa of cubical box is greater and by 40cm²
Tsa of cube- 6l²--6(10)²-- 600cm²
Tsa of cuboidal box-2(lb+bh+hl)
2(12.5*10+10*8+8*12.5)
2(125+80+100)
2(305)
610cm²
So the tsaa of cubical box is smaller and by 10cm2