9. The rational number between -1/5 and -215 is
a 4
b-1/4
C-3/10
d-7/25
Answers
Answer:
Given :
Dimensions of floor = 8 m × 7 m
Height of the room = 4 m
\begin{gathered} \\ \rule{200pt}{3pt}\end{gathered}
To Find :
Find the Area of four walls .
\begin{gathered} \\ \rule{200pt}{3pt}\end{gathered}
Solution :
~ Formula Used :
Total Surface Area :
{\purple{\dashrightarrow}} \: \: {\underline{\overline{\boxed{\red{\pmb{\sf{ LSA{\small_{(Cuboid)}} = 2(lb + bh + hl) }}}}}}}⇢
LSA
(Cuboid)
=2(lb+bh+hl)
LSA
(Cuboid)
=2(lb+bh+hl)
Area :
{\purple{\dashrightarrow}} \: \: {\underline{\overline{\boxed{\red{\pmb{\sf{ Area{\small_{(Rectangle)}} = L \times B }}}}}}}⇢
Area
(Rectangle)
=L×B
Area
(Rectangle)
=L×B
Where :
➳ TSA = Total Surface Area
➳ L = Length
➳ B = Breadth
➳ H = Height
➳ A = Area
\begin{gathered} \\ \qquad{\rule{150pt}{1pt}}\end{gathered}
~ Calculating the TSA of Room :
\begin{gathered} {\longmapsto{\qquad{\sf{ TSA{\small_{(Room)}} = 2(lb + bh + hl) }}}} \\ \\ \ {\longmapsto{\qquad{\sf{ TSA{\small_{(Room)}} = 2[( 8 \times 7) + (7 \times 4) + (4 \times 8)] }}}} \\ \\ \ {\longmapsto{\qquad{\sf{ TSA{\small_{(Room)}} = 2( 56 + 28 + 32) }}}} \\ \\ \ {\longmapsto{\qquad{\sf{ TSA{\small_{(Room)}} = 2 \times 116 }}}} \\ \\ \ {\qquad{\textsf{ Lateral Surface Area of the Room = {\pink{\sf{ 232 \: m² }}}}}}\end{gathered}
⟼TSA
(Room)
=2(lb+bh+hl)
⟼TSA
(Room)
=2[(8×7)+(7×4)+(4×8)]
⟼TSA
(Room)
=2(56+28+32)
⟼TSA
(Room)
=2×116
Lateral Surface Area of the Room = 232 m²