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Find the Length of Each Edge of a Cube, If Its Volume is : (I) 216 Cm3 (Ii) 1.728 M3 - Mathematics

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Question

Find the length of each edge of a cube, if its volume is :
(i) 216 cm3
(ii) 1.728 m3

Sum
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Solution

(i)

`("Edge")^3` = Volume of a cube

`("Edge")^3` = 216 cm3

⇒ Edge = `(216)^(1/3)`

⇒ Edge = `(3 xx 3 xx 3 xx 2 xx 2 xx 2)^(1/3)`

⇒ Edge = `3 xx 2`

⇒ Edge = 6 cm.

(ii)

`("Edge")^3` = Volume of a cube

`("Edge")^3` = 1.728 m3

⇒ `("Edge")^3 = 1.728/1.000 = 1728/1000`

⇒ Edge = `(1728/1000)^(1/3)`

⇒ Edge = `((2 xx 2xx 2 xx 2 xx 2 xx 2 xx 3 xx 3 xx 3)/(10 xx 10 xx 10))^(1/3)`

⇒ Edge = `(2 xx 2 xx 3)/10`

⇒ Edge = `12/10`m

⇒ Edge = 1.2 m

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Chapter 21: Surface Area, Volume and Capacity - Exercise 21 (A) [Page 238]

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Selina Concise Mathematics [English] Class 8 ICSE
Chapter 21 Surface Area, Volume and Capacity
Exercise 21 (A) | Q 6 | Page 238

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