If the heights of two cones are in the ratio of 1:4 and the radii of their bases are in the ratio 4:1, then the ratio of their volumes is (a)   1:2        (b)  2:3         (c)  3:4      (d)  4:1

Explanation

As, we know that the volumes of a cone is `1/3pir^2h`

`therefore` ratio of volumes of two cones

`V^'/V^('')`=`(1/3pi(4)^2(1))`/`(1/3pi(1)^2(4))`

`V^'/V^('')`=`16/4`

`V^'/V^('')`=`4:1`

Hence, option(d) is correct.