Question

Mary wants to decorate her Christmas tree. She wants to place the tree on a wooden box covered with coloured paper with picture of Santa claus on it . She must know the exact quantity of paper to buy for this purpose . If the box has length, breadth, and height as 80cm, 40cm and 20cm respectively how many square sheets of paper of side 40cm would she required. ​

Answer 1

Step-by-step explanation:

$\frak Given = \begin{cases} &\sf{Length\ of\ the\ box\ =\ 80cm.} \\ &\sf{Breadth\ of\ the\ box\ =\ 40cm.} \\ &\sf{Height\ of\ the\ box\ =\ 20cm.} \end{cases}$

To find:- We have to find the number of square sheets of paper required of side 40cm ?

__________________

$\frak{\underline{\underline{\dag As\ we\ know\ that:-}}}$

$\sf\pink{\underline{The\ surface\ area\ of\ the\ box\ =\ 2(lb\ +\ bh\ +\ hl).}}$

__________________

$\frak{\underline{\underline{\dag By\ substituting\ the\ values,\ we\ get:-}}}$

$\sf : \implies {2\ [(80\ ×\ 40)\ +\ (40\ ×\ 20)\ +\ (20\ ×\ 80)]\ cm²} \\ \\ \sf : \implies {2\ [3200\ +\ 800\ +\ 1600]\ cm²} \\ \\ \sf : \implies {2\ ×\ 5600\ cm²} \\ \\ \sf : \implies {\purple{\underline{\boxed{\bf 11200cm².}}}}\bigstar$

$\frak{\underline{\underline{\dag The\ area\ of\ each\ sheet\ of\ the\ paper:-}}}$

$\sf : \implies {40\ ×\ 40\ cm²} \\ \\ \sf : \implies {\purple{\underline{\boxed{\bf 1600cm².}}}}\bigstar$

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$\sf \therefore {\underline{Number\ of\ sheets\ required:-}}$

$\sf : \implies {\dfrac{surface\ area\ of\ box}{area\ of\ one\ sheet\ of\ paper}} \\ \\ \sf : \implies {\dfrac{11200}{1600}} \\ \\ \sf : \implies {\purple{\underline{\boxed{\bf 7\ sheets.}}}}\bigstar$

Hence:-

$\sf \therefore {\underline{So,\ she\ would\ require\ 7\ sheets.}}$

Answer 2

$\huge\bold{\mathtt{\red{A{\pink{N{\green{S{\blue{W{\purple{E{\orange{R}}}}}}}}}}}}}$

Step-by-step explanation:

$Step-by-step explanation:</p><p></p><p>[tex]\frak Given = \begin{cases} &\sf{Length\ of\ the\ box\ =\ 80cm.} \\ &\sf{Breadth\ of\ the\ box\ =\ 40cm.} \\ &\sf{Height\ of\ the\ box\ =\ 20cm.} \end{cases}$

To find:- We have to find the number of square sheets of paper required of side 40cm ?

__________________

$\frak{\underline{\underline{\dag As\ we\ know\ that:-}}}$

$\sf\pink{\underline{The\ surface\ area\ of\ the\ box\ =\ 2(lb\ +\ bh\ +\ hl).}}$

__________________

$\frak{\underline{\underline{\dag By\ substituting\ the\ values,\ we\ get:-}}}$

$\sf : \implies {2\ [(80\ ×\ 40)\ +\ (40\ ×\ 20)\ +\ (20\ ×\ 80)]\ cm²} \\ \\ \sf : \implies {2\ [3200\ +\ 800\ +\ 1600]\ cm²} \\ \\ \sf : \implies {2\ ×\ 5600\ cm²} \\ \\ \sf : \implies {\purple{\underline{\boxed{\bf 11200cm².}}}}\bigstar$

$\frak{\underline{\underline{\dag The\ area\ of\ each\ sheet\ of\ the\ paper:-}}}$

$\sf : \implies {40\ ×\ 40\ cm²} \\ \\ \sf : \implies {\purple{\underline{\boxed{\bf 1600cm².}}}}\bigstar$

__________________

$\sf \therefore {\underline{Number\ of\ sheets\ required:-}}$

$\sf : \implies {\dfrac{surface\ area\ of\ box}{area\ of\ one\ sheet\ of\ paper}} \\ \\ \sf : \implies {\dfrac{11200}{1600}} \\ \\ \sf : \implies {\purple{\underline{\boxed{\bf 7\ sheets.}}}}\bigstar$

Hence:-

$\sf \therefore {\underline{So,\ she\ would\ require\ 7\ sheets.}}$[/tex]