Find the radius of frustum of cone given that volume is 1199m3 with a height of 42cm and one of the radius 3.5 m

Find the radius of frustum of cone given that volume is 1199m3 with a height of 42cm and one of the radius 3.5 m.

(a)          2.2 m

(b)          2.5 m

(c)           2.8 m

(d)          3.2 m

Sol: