Question

In Fig. 5, from a cuboidal solid metallic block, of dimensions 15cm ✕ 10cm ✕ 5cm, a cylindrical hole of diameter 7 cm is drilled out. Find the surface area of the remaining block [Use

`pi=22/7`]

Answer 1

Surface area of the remaining block = Surface area of the cuboid + Curved surface area of cylinder − 2 × Area of base of cylinder

`=2(15xx10xx+10xx5+15xx5)+(2xx22/7xx7/2xx5)-(2xx22/7xx7/2xx7/2)`

= 583 cm²

Thus, the surface area of the remaining block is 583 cm^2.