Question

The slant height of a frustum of a cone is 4 cm and the perimeters of its circular ends are 18 cm and 6 cm
respectively. Find the curved surface area of the frustum​

Answer 1

Answer:

Slant height =4cm

Perimeter of one circular end = 18 cm

2pie× R = 18

Pie× R = 18/2

R= 9/pie

Now, the perimeter of second end = 6cm

2pie×r= 6

Pie×r= 6/2

r= 3/ pie

CSA= pie ×l (R+r)

pie× 4 ( 9/pie + 3/pie)

48cm2

Answer 2

Answer:

Slant height =4cm

Perimeter of one circular end = 18 cm

2pie× R = 18

Pie× R = 18/2

R= 9/pie

Now, the perimeter of second end = 6cm

2pie×r= 6

Pie×r= 6/2

r= 3/ pie

CSA= pie ×l (R+r)

pie× 4 ( 9/pie + 3/pie)

48cm2