Answer:
Hence required paper for entire shape will be L[L+2(2H+H1)] Sq.cm
Step-by-step explanation:
Given:
A block with rectangular prism at bottom and square pyramid at top.
To Find:
Paper required to cover whole block
Solution:
We know that block consist of two different shapes as prism and pyramid.
So paper covering will be for surface.
hence we required surface area for rectangular prism and square pyramid.
(Refer the attachment)
Now only outer surface should be consider in order to cover the shape.
for square pyramid its length and breadth will be the same .
let L be length and B be breadth and h be height
<em>So total no.of faces will be 6 but on top there is prism placed so top surface will be neglected for the calculations</em>.
H<em>ence No.of faces will be 5.</em>
So total surface area for square pyramid will be
=L*W+2(L*H+W*H)
Here L=W as it is square pyramid
=L^2+4(L*H)
Now for the Prism surface it will have 4 triangles placed on with base as length of pyramid(as shown in fig) and height be H1
So Total area for Prism will be
=4( Area of triangles)
=4*1/2*base*height)
=2*base *height
=2*L*H1
So required Paper will be
Total surface area=Surface are of pyramid+ Area of 4 triangles.
=L^2+4(L*H)+2*L*H1
=L[L+2(2H+H1)].
