A cuboid of dimension 7 cm * y cm * 15 cm is given. Find the minimum value of y so that at least two cones of maximum volume having some dimensions and a height of 15 cm, can be cut from this solid.
OPtion
1) 7 cm
2) 7.5 cm
3) 3 cm
4) 12.5 cm
5) 15 cm
6) 8.5 cm
7) 10.5 cm
8) 9 cm
9) 3.5 cm
10)11.5 cm
Solution
By using figure
For y to be minimum
Max volume cone will have a radius of 3.5 cm.
Thus, minimum value of x
= 7+3.5
= 10.5 cm
Option 7)