Question

Calculate the total surface area of frustum cone given below :

• A. 57 $\pi c{m}^2$
• B. 67 $\pi c{m}^2$
• C. 77 $\pi c{m}^2$
• D. 87 $\pi c{m}^2$

Answer 1

Answer: (B)

67 $\pi c{m}^2$

Total surface area = $\pi (R+r)s+\pi R^2+\pi r^2$
= $\pi (4+1)10+\pi 4^2+\pi 1^2$

= $50\pi +16\pi +\pi$

= $67\pi c{m}^2$