Question

the internal dimensions of cuboidal room are 13 into 9 metre into 4.5 metre find the total cost of whitewashing all four walls of the room if the cost of whitewashing is rupees 7 per metre^2​

Answer 1

Given :-

• Length of room,l = 13m
• breadth of room, b = 9m
• height of room, h = 4.5m
• rate of whitewashing = Rs.7 per m²

To Find :-

• cost of whitewashing four walls of the room ?

Solution :-

we know that,

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

$\bold{: \implies 2 \times (13 + 9) \times 4.5} \\ \\ \bold{: \implies 2 \times 22 \times 4.5} \: \: \: \: \: \: \: \: \: \: \: \\ \\ \bold{: \implies198.0 \: {m}^{2} } \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \:$

so, area of four walls is 198 m²

now,

cost of whitewashing = area of four walls × rate

$\bold{: \implies 198 \times 7 } \\ \\ \bold{: \implies 1386 \: \: \: \: \: }$

hence, cost of whitewashing of four walls is Rs. 1386

Answer 2

Answer:

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