A sphere of radius 10.4 cm. is melted to form spheres of radius 2.75 cm. Calculate the number of sph

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07 Oct 2011 sphere

A sphere of radius 10.4 cm. is melted to form spheres of radius 2.75 cm. Calculate the number of spheres of small size

OPtion

1) 40
2) 44
3) 45
4) 48
5) 54
6) 60
7) 62
8) 64
9) 66
10) none of these

Solution

volume of bigger sphere is proportional to (10.4)^3
volume of smaller sphere is proportional to (2.75)^3
so no. of smaller spheres = (10.4)^3/(2.75)^3 = 54

Correct Option: 5 Best Solution (4)

Dr.Dipin Singh   12 years AGO

volume of sphere = (4/3)*Pi* (r^3)

so no of spheres of small size = [(10.4^3]/[(2.75)^3]= 54.088

so 54 smaller spheres are possible.

so option 5.

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Balakumaran N.A   12 years AGO

No. of Spheres = volume of big sphere/volume of small sphere;
volume of sphere= (4/3)*3.14*r^3;
so, n=4709/87(approximately) = 54.

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Rush   12 years AGO

volume of big sphere of radius 10.4 is 3.14*10.4*10.4*10.4=3532.07296
(3.14 is value of pi)
volume of small sphere of radius 2.75 is 3.14*2.75*2.75*2.75=65.3021875
so 65.3021875 is volume of 1 sphere
then 3532.07296 is volume of ? spher
so, 3532.07296/65.3021875 = 54
so, answer is 54

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Sneha Latha M   12 years AGO

finding the volumes of two spheres and dividing them gives the number of spheres can be formed with 2.75 radius. the answer is 54.

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