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

Solution:

Given, dimensions of a cuboid are 5 cm, 2 cm, 5 cm

Volume of cuboid = length × breadth × height

= 5 × 2 × 5

= 5² × 2 cm³

As there are two 5's and one 2, to make the volume of cuboid as a cube number we need to multiply it by 5 × 2 × 2

Newly formed cube = 5² × 2¹ × 5 × 2 × 2 = 5³ × 2³ cm³

Number of cuboids required = Volume of cube/Volume of cuboid

Number of cuboids required = 5³ × 2³ / 5² × 2 = 5 × 2 × 2 = 20

∴ Number of cuboids required to make a cube = 20

☛ Check: NCERT Solutions for Class 8 Maths Chapter 7

Video Solution:

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

NCERT Solutions for Class 8 Maths Chapter 7 Exercise 7.1 Question 4

Summary:

Parikshit makes a cuboid of plasticine of sides 5 cm, 2 cm, 5 cm. The number of plasticine cuboids that Parikshit needs to form a cube is 30

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