Question

A solid cone of height 24 cm and radius of its base 8 cm is melted to form a solid cylinder of radius 6 cm and height 6 cm. In the whole process what
percent of material is wasted

Answer 1

//cone//
hieght = h = 24cm
radius = r = 8cm
volume = v = ?

v = πr²h/3
v = π(8)²×24/3
v = π(64)(8)
v = 512π cm³
_______________
//cylinder//

height = h = 6cm
radius = r = 6cm
volume = ?
v = πr²h
v = π(6)²(6)
v = 216πcm³
___________

wasted meterial
= volume of cone - volume of cylinder
= 512π-216π
= 296π cm³
___________

percentage

512π : 100 :: 296π : x

296π×100/512π = x

296×100/512 = x

0.5781×100 = x

57.81 % (approximate)= x

so percentage of wasted material is 57.81%