Elitmus
Exam
Numerical Ability
Area and Volume
Find the maximum volume a right circular cone that can fit inside a cuboid of size 10x15x12.
Read Solution (Total 3)
-
- Since base circle will be in 2-D and so radius will be 5 in 10x12 plane and height will be 15 for the vol to be maximum.
So max possible vol is
1/3*π*5*5*15= 125π
Now I'll make some comments, it will be helpful to visualize the situation.
1. why 15/2 will not be r because it will be a circle in 2D and none of the other side is 15 or greater.
2. If you will take r=6 then height can't be 15. Because again in 10x12 plane circle is not possible with r=6. If you will take r=6 then height will be 10. Then ans will be 120π. - 7 years agoHelpfull: Yes(11) No(0)
- formula is 1/3 pie*r^2*h
so clearly if r will be max so volume will be max
so take breadth as a base of cone the radius will be= 15/2 and take width as a hieght
volume will =1/3*15/2*15/2*12*pie
ans would be 225pie - 7 years agoHelpfull: Yes(1) No(10)
- put r=6 and h=15 calculate
volume of cone as = 1/3*r*r*h*pie
answer would be=180pie - 7 years agoHelpfull: Yes(0) No(17)
Elitmus Other Question
Let S be the number of 6 digit numbers formed by using 1,2,3,4,5,6 without repetition and R be the number of 5 digit numbers formed by 1,2,3,4,5,6 without repetition. Find S-R.
Six bangles of different colors having radius 4 cm each are placed inside a circle. The bangles are just touching each other. The circle touches them outside. Find the radius of the circle.