1. Volume of a frustum of a cone = 1/3 x πh x (r12 + r22 + r1r2)
2. Curved surface area of a frustum of a cone = πl(r1 + r2) where l = √h² - (r1 + r2)²
3. Total surface area of frustum of a cone = πl(r1 + r2) + π(r12 + r22) where 
h = vertical height of the frustum, 
l = slant height of the frustum 
r1 and r2 are radii of the two bases (ends) of the frustum.
    

NOTE: Basic formula (i.e, Cylinder, Cone, Sphere etc.) available in Class-9 Surface Area & Volume Chapter. Click Here