Question

(B) Find the total surface area of cubes having the following sides.
(i) 3 cm (ii) 5 cm
(iii) 7.2m​

Answer 1

$\huge{\underline{\underline{\tt{\blue{Qᴜᴇsᴛɪᴏɴ\:I:}}}}}$

• $\sf{3\:cm}$

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$\huge{\underline{\underline{\bf{\blue{Fɪɴᴅ\::}}}}}$

• $\sf{Total\:Surface\:Area\:of\:Cubes}$

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$\huge{\underline{\underline{\bf{\blue{Sᴏʟᴜᴛɪᴏɴ\::}}}}}$

• ${\underbrace{\mathfrak{\red{Total\:Surface\:Area\:of\:Cube\:\leadsto\:6l}^{\red{2}}}}}$

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$\:\:\:\:\:\:\:\::\:\Longrightarrow\sf\:{6\:\times\:(\:3\:)}^{2}$

$\:\:\:\:\:\:\:\::\:\Longrightarrow\sf\:{6\:\times\:9}$

$\:\:\:\:\:\:\:{\purple{\bold{\dag}}}\:{\underline{\sf{So,\:Total\:Surface\:Area\:is\:{\bold{\mathfrak{\green{54\:sq.\:cm}}}}}}}$

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$\:\:\:\:\:\:\:\:\:\:\:\:━━━━━━━━━━━━━━━$

$\huge{\underline{\underline{\tt{\blue{Qᴜᴇsᴛɪᴏɴ\:II:}}}}}$

• $\sf{5\:cm}$

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$\huge{\underline{\underline{\bf{\blue{Fɪɴᴅ\::}}}}}$

• $\sf{Total\:Surface\:Area\:of\:Cubes}$

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$\huge{\underline{\underline{\bf{\blue{Sᴏʟᴜᴛɪᴏɴ\::}}}}}$

• ${\underbrace{\mathfrak{\red{Total\:Surface\:Area\:of\:Cube\:\leadsto\:6l}^{\red{2}}}}}$

${ }$

$\:\:\:\:\:\:\:\::\:\Longrightarrow\sf\:{6\:\times\:(\:5\:)}^{2}$

$\:\:\:\:\:\:\:\::\:\Longrightarrow\sf\:{6\:\times\:25}$

$\:\:\:\:\:\:\:{\purple{\bold{\dag}}}\:{\underline{\sf{So,\:Total\:Surface\:Area\:is\:{\bold{\mathfrak{\green{150\:sq.\:cm}}}}}}}$

${ }$

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$\huge{\underline{\underline{\tt{\blue{Qᴜᴇsᴛɪᴏɴ\:III:}}}}}$

• $\sf{7.2\:m}$

${ }$

$\huge{\underline{\underline{\bf{\blue{Fɪɴᴅ\::}}}}}$

• $\sf{Total\:Surface\:Area\:of\:Cubes}$

${ }$

$\huge{\underline{\underline{\bf{\blue{Sᴏʟᴜᴛɪᴏɴ\::}}}}}$

• ${\underbrace{\mathfrak{\red{Total\:Surface\:Area\:of\:Cube\:\leadsto\:6l}^{\red{2}}}}}$

${ }$

$\:\:\:\:\:\:\:\::\:\Longrightarrow\sf\:{6\:\times\:(\:7.2\:)}^{2}$

$\:\:\:\:\:\:\:\::\:\Longrightarrow\sf\:{6\:\times\:51.84}$

$\:\:\:\:\:\:\:{\purple{\bold{\dag}}}\:{\underline{\sf{So,\:Total\:Surface\:Area\:is\:{\bold{\mathfrak{\green{311.04\:sq.\:m}}}}}}}$

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$\:\:\:\:\:\:\:\:\:\:\:\:━━━━━━━━━━━━━━━$