- How many tiles of 20cm
^{2}will be required?

- To have a footpath 1m wide.

- Carried around the outside of grassy plot 24m long and 14m broad.

Note: This question was asked in Competitive Examination (CSS) – 2021 General Science & Ability under Section – B [Q. 6. (b)].

## Explanation

Following things are needed to discuss here.

- Area required to be paved.
- Number of tiles.

Following things are given.

- Size of a tile (20cm
^{2}). - Dimension of grassy plot (24m long and 14m broad).
- Extension in footpath (1m wide).

First, we will calculate the area (in centimeters) required to be paved and then dividing it with the area of a tile (20cm^{2}) we can figure out easily the total number of tiles.

## To Find

Number of tiles = ?

## Solution

__Method I__

It is clear from the picture that we have four rectangles whose area in square centimeter is required to calculate.

__Case I__

Area of first rectangle = 26m x 1m

Area of first rectangle = 26m^{2}

Area of first rectangle in square centimeters = (26 x 100 x 100) cm^{2}

Area of first rectangle in square centimeters = 260000 cm

^{2}

__Case II__

Area of second rectangle = 26m x 1m

Area of second rectangle = 26m^{2}

Area of second rectangle in square centimeters = (26 x 100 x 100) cm^{2}

Area of second rectangle in square centimeters = 260000 cm

^{2}

__Case III__

Area of third rectangle = 14m x 1m

Area of third rectangle = 14m^{2}

Area of third rectangle in square centimeters = (14 x 100 x 100) cm^{2}

Area of third rectangle in square centimeters = 140000 cm

^{2}

__Case IV__

Area of fourth rectangle = 14m x 1m

Area of fourth rectangle = 14m^{2}

Area of fourth rectangle in square centimeters = (14 x 100 x 100) cm^{2}

Area of fourth rectangle in square centimeters = 140000 cm

^{2}

Now;

Total area = (260000 + 260000 + 140000 + 140000) cm^{2}

Total area = 800000 cm^{2}

Size of a tile = 20 cm^{2}

Number of tiles = 800000/20

**Number of tiles = 40000 answer**

__Method II__

Total area of grassy plot including footpath = 26 x 16

Total area of grassy plot including footpath = 416 m^{2}

Area of grassy plot excluding footpath = 24 x 14

Area of grassy plot excluding footpath = 336 m^{2}

Area of footpath = 416 – 336

Area of footpath = 80 m^{2}

Area of footpath in centimeters = (80 x 100 x 100) cm^{2}

Area of footpath in centimeters = 800000 cm^{2}

Size of a tile = 20 cm^{2}

Number of tiles = 800000/20

**Number of tiles = 40000 answer**

## Conclusion

40000 tiles of 20cm^{2} will be required to have a footpath 1m wide carried around the outside of grassy plot 24m long and 14m broad.