Question

a room 14m long 9.5m broad and 4m high has 1 door 2m by 1.5m and three windows 1.4m by 75cm. find cost of distempering walls room from inside at the rate of rs. 18 per m

Answer 1

Before, finding the answer. Let's find out on how we find answer.

• First, we must find the area of four walls by the formula of :

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

• Then, we must find the area of door and windows by the formula of :

$\boxed{\sf Area \: of \: window \: and \: door = l \times b }$

• Now, we must add the area of window and door. And subtract it from area of four wall.
• At last, We must multiply the area with the cost of distempering.

________________________

Given :

• Measure of Room = 14m, 9.5m and 4m
• Measure of Door = 2m and 1.5 m.
• Measure of Windows = 1.4m and 75 cm.

To find :

• cost of distempering

Solution :

Area of four walls = (2 × l) + (2 × b) × h

                              = (2 × 14) + (2 × 9.5) × 4

                              = 28 + 19 × 4 m²

                              = 47 × 4 m²

                              = 188 m²

∴ the area of four walls is 188 m².

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Area of Door = l × b

                      = 2 × 1.5 m²

                      = 3.0 m²

∴ the area of door is 3 m².

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→ Converting cm to m.

• 75 cm = 0.75 m.

Area of windows = l × b

                            = 1.4 × 0.75 m²

                            = 1.05 m²

Area of three windows = area of window × 3

                                      = 1.05 × 3 m²

                                      = 3. 15 m²

∴ the area of 3 windows is 3.15 m²

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Cost of wall to be distempering = area of four walls - (area of one door + area of the three windows)

                                                    = 188 - (3 + 3.15)

                                                    = 188 - 6.15 m²

                                                    = 181.85 m²

∴ total area is 181.85 m².

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Cost for Distempering = area × cost

                                     = 181.85 × 18

                                     = ₹ 3273.3

∴Total cost is ₹ 3273.3