Question

A man is in talks with a painter. He wants to two of his walls painted. The cost of painting is Rs10 per $c{m}^2$.How much money is required by him to paint a rectangular wall of length 400 cm and breadth 900 cm and a circular wall of diameter 126 cm? [4 MARKS]

Answer 1

Formula: [1 Mark]
Steps: [2 Marks]
Answer: [1 Mark]

Given that
The cost of painting is Rs10 per$c{m}^2$.
The length of the rectangular wall=400 cm
The breadth of the rectangular wall=900 cm

Area of the rectangle = length $\times$ breadth
On substituting the values we get

Area of the rectangle = (400) $\times$ (900)

= 360000 $c{m}^2$

Money required to paint the rectangular wall = (10) $\times$ (360000)

= Rs.3600000

The diameter of the circular wall= 126 cm.
Radius of the wall, $r$=$1262$= 63 cm
The area a circle is given by, Area=$\pi \times r^2$
On substituting the values we get
Area of the circular wall=$\frac{22}{7}\times 63\times 63$=12474 (cm^2\)
Money required to paint the circular wall=12474$\times$10=Rs 124740

The total cost of painting=3600000+124740 = Rs 3724740
Hence, the total cost of painting the walls is Rs 37,24,740.