A metal cylinder of base 5 cm and height 12 cm is melted to make n solid cones of height 1 cm and ba

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16 Nov 2016 Value of n is

A metal cylinder of base 5 cm and height 12 cm is melted to make n solid cones of height 1 cm and base radius 1 mm the value of n is:

OPtion

1) 450
2) 1350
3) 1500
4) 1300
5) 9000
6) 90000
7) 12500
8) 25600
9) 18500
10)None of these

Solution

n = number of cones = volume of cylinder/ volume of cone
= (pi*5*5*12)/(pi/3*10*10)
= 90000

Option 6)

Correct Option: 6 Best Solution (4)

SARATCHANDRAN   8 years AGO

3.14*R*R*H=n*3.14.r*r*h/3
therefore 5*5*12=n*1*.1*.1*1/3
so n=90000

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DEVANSH SUBNANI   8 years AGO

pi*r*r*h=n*(1/3)*pi*r*r*h
=>5*5*12=n*(1/3)*(0.1)^2*1
=>n=90,000
Option 6)

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Pragati Rode   8 years AGO

Volume of Cylinder = pi*r^2*h
volume of cone = 1/3(pi*r^2*h)

value of n = volume of cylinder /volume of Cone
=pi*r^2*h/(1/3(pi*r^2*h))
=r^2*h/(1/3(r^2*h))
=5 * 5*12 * 3/0.1*0.1*1
convert mm to cm 1mm = 0.1cm
value of n = 900/0.01
=90000
so option is 6

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divyasree   8 years AGO

volume of cylinder=volume of cone
πr^2h=πr^2(h÷3)
0n solving it we got ratio of 1:90000

Like? Yes | No (1)