Question

if the cost of white washing a wall is 9120 rupees at the rate of 10 rupees per m . then find the area of the wall to be painted. also find its length if its breadth is 16m ​

Answer 1

AnswEr :

$\bold{Given} \begin{cases}\sf{Cost \:of \:white \: washing=Rs.\:9120} \\ \sf{Rate=Rs. \:10@ {m}^{2} }\\ \sf{Breadth=16m}\end{cases}$

$\rule{300}{1}$

• S O M E ⠀I N F O R M A T I O N S :

1) Whenever Question is about Cost of White Washing, Cost of Painting, Cost of Carpeting. Simply Understand it is talking about AREA OF SHAPE.

One can also understand from the unit of Rate Given, (m²) in this Case. So It is must talking about AREA.

2) But whenever Question is about Cost of Fencing, or any Cost regarding Boundaries. Simply Understand it is talking about PERIMETER OF SHAPE.

One can also understand from the unit of Rate Given, like (m, cm). So It is must talking about PERIMETER.

$\rule{300}{2}$

• Let's Head to the Question Now :

$\longrightarrow \tt Cost \:of \:White \:Washing = Area \times Rate \\ \\ \longrightarrow \tt Rs. 9120= Area \times 10 \\ \\\longrightarrow \tt \cancel\dfrac{9120}{10} = Area \\ \\\longrightarrow \blue{\tt Area = 912 {m}^{2}}$

⠀

∴ Area of wall to be painted is 912 m².

$\rule{300}{1}$

• L E N G T H ⠀O F ⠀W A L L :

$\Longrightarrow \tt Area = 912 {m}^{2} \\ \\ \Longrightarrow \tt Length \times Breadth= 912 {m}^{2} \\ \\ \Longrightarrow \tt Length \times 16m = 912 {m}^{2} \\ \\ \Longrightarrow \tt Length = \cancel\dfrac{912 {m}^{2} }{16m} \\ \\ \Longrightarrow \blue{\tt Length = 57m}$

⠀

∴ Therefore, Length of the wall is 57m.

#answerwithquality #BAL

Answer 2

Answer:

Area = 9120 ÷ 10

= 912 m²

b = 16 m

=> A = l*b

=> l = 912 ÷ 16

=> l = 57 m