Question

The length, breadth and height of a room are 5m,4m and 3m respectively, find the cost of white washing the walls of the room and the ceiling at the rate of Rs.7.50 per m²

Answer 1

Answer :-

Length = 5 m

Breadth = 4 m

Height = 3 m

Area of four walls = 2 ( lh + bh )

=》 Area = 2 ( 5 × 3 + 4 × 3 )

=》 Area = 2 ( 15 + 12 )

=》 Area = 2 × 27

=》 Area = $\tt{54\: m^{2}}$
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Area of the roof = l × b

=》 Area = 5 × 4

=》 Area = $\tt{20\:m^{2}}$
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Total area for white washing = 54 + 20 = $\tt{74\:m^{2}}$
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Cost for 1 sq. m = Rs. 7.5

Cost for 74 sq. m = 74 × 7.5 = Rs. 555
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Therefore, answer is $\tt{\huge{Rs. 555}}$

Answer 2

$\mathfrak{\huge{Hi !}}$

Given Length of the room = 5m

Breadth of the room = 4 m

Height of the room = 3 m

Area of the four walls will be = 2 ( bh + lh )

Area = 2 ( 12 + 15 )

Area = 2 ( 27 )

$\sf{Area = 54 \:sq. m}$

Area of the roof = lb

$\sf{Area = 20 \:sq. m}$

Total area = 54 + 20 = 74 sq. m

Cost = Rs. 7.5 /-

$\sf{\huge{\underline{Cost= Rs. 555}}}$