Question

The surface area of a cuboid 15 cm broad and 10 cm high is 1300 cm. Find Its length.​

Answer 1

Answer:

TSA= 1300CM^2

TSA= 2(LB +BH +HL)

1300 = 2(L*15 +15*10 +10*L)

1300 = 2(15L +150 +10L)

2(25L +150)

50L +300

1300 -300 =50L

1000/50 = L

L =20

Step-by-step explanation:

Answer 2

$\: \: \boxed{\boxed{\bf{\mapsto \: \: \: Question}}}$

The surface area of a cuboid 15 cm broad and 10 cm high is 1300 cm. Find Its length.

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$\: \: \boxed{\boxed{\bf{\mapsto \: \: \: Answer}}}$

The surface area of a cuboid 15 cm broad and 10 cm high is 1300 cm. it's length will be 20 cm

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$\: \: \boxed{\boxed{\bf{\mapsto \: \: \: Solution}}}$

Given,

» The surface area of a cuboid is 15 cm broad

» The surface area of a cuboid is 10 cm high

» The surface area of a cuboid is 1300 cm²

To find ,

» length of surface area of a cuboid is = ?

~ Let's solve it ,

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Let , length of the surface are of the square be x

so

$\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\\\;\large{ \longrightarrow{\sf surface \: area \: of \: cuboid \: = 2(lb + bh + lh)}}\end{gathered}\end{gathered} \end{gathered}\end{gathered} \end{gathered}$

$\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\\\;\large{ \longrightarrow{\sf 1300\: = 2((l \times 15 )+ (15 \times 10) +( l \times 10))}}\end{gathered}\end{gathered} \end{gathered}\end{gathered} \end{gathered}$

$\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\\\;\large{ \longrightarrow{\sf 1300\: = 2(15 l+ 150 + 10l)}}\end{gathered}\end{gathered} \end{gathered}\end{gathered} \end{gathered}$

$\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\\\;\large{ \longrightarrow{\sf \dfrac{1300}{2} = (15 l+ 150 + 10l)}}\end{gathered}\end{gathered} \end{gathered}\end{gathered} \end{gathered}$

$\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\\\;\large{ \longrightarrow{\sf 650\: = 150 + 25l}}\end{gathered}\end{gathered} \end{gathered}\end{gathered} \end{gathered}$

$\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\\\;\large{ \longrightarrow{\sf 25l\: = 500 \: (as \: 650 - 150)}}\end{gathered}\end{gathered} \end{gathered}\end{gathered} \end{gathered}$

$\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\\\;\large{ \longrightarrow{\sf l\: = \dfrac{500}{25} }}\end{gathered}\end{gathered} \end{gathered}\end{gathered} \end{gathered}$

$\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\begin{gathered}\\\;\large{ \Longrightarrow{\sf l\: = 20 }}\end{gathered}\end{gathered} \end{gathered}\end{gathered} \end{gathered}$

$\: \: \boxed{\boxed{\bf{\mapsto \: \: \: hence , length = \underline{20 \: cm}}}}$