Question

09. Parikshit makes a cube of plasticine of sides 5 cm, 2cm, 5cm. How many such
cuboids will he need to form a cube?
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Answer 1

Now, the volume of the cuboid is = (5*2*5) cubic cm = 50 cubic cm. and, the volume of the new cube is = (10*10*10) cubic cm = 1000 cubic cm. Therefore, he need (1000/50) cuboids, i.e., 20 cuboids.

Answer 2

$\star\:\:\:\bf\large\underline\blue{Given:—}$

Parikshit makes a cube of plasticine of sides 5 cm ,2 cm and 5 cm

$\star\:\:\:\bf\large\underline\blue{To\:find:–}$

Number of cuboids will he need to form a cube = ?

$\star\:\:\:\bf\large\underline\blue{Solution:–}$

L.C.M of 5 and 2 gives the dimension of cube to be formed.

L.C.M of 2 and 5 is 10

Volume of cuboid = 5×5×2 cm³ = 50 cm³

Volume of bigger cube = 10³ cm³= 1000 cm³

Number of cuboids required to make bigger cube

= $\frac{volume\:of\:cube}{volume\:of\:cuboids}$

$= \frac{1000}{50} \\ = 20$

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