Question

find the cost of white washing the inner four walls of room at rate of 10per square metre​

Answer 1

$\huge\blue{Given}$ :-

Length = 8m

Breadth = 4.5m

Height = 2.8m

$\bold{\boxed{\huge{\boxed{\orange{\small{\boxed{\huge{\red{\bold{\:Answer}}}}}}}}}}$

$area \: of \: four \: walls \: = 2(l + b) \times h$

$area = 2(8 + 4.5) \times 2.8$

$area = 70m ^{2}$

Now,

$area \: of \: door \: with \: semicircle \: =$

$= = (1.4 \times 2) + \pi(0.7) \\ \\ = = 2.8 \: + 2.2 \\ \\ = = \: 5m^{2}$

Now,

$area \: of \: two \: rectangular \: window \: = = \\ \\ 2(2 \times 1.5) \\ \\ 6m ^{2}$

so, the area of white washing the inner four walls = Total walls area -(Door+2window)

=== 70-(5+6)

=== $\large\red{\boxed{\sf </strong><strong>5</strong><strong>9</strong><strong>\:{m}^{2} }}$

$cost \: of \: white \: washing \: = 10 \times 59$

$\large\red{\boxed{\sf 59</strong><strong>0</strong><strong>\:</strong><strong>Rs</strong><strong>.</strong><strong>}}$

$\huge\blue{</strong><strong>THANKS</strong><strong>}$