# Floor of a room is of dimensions 5 m × 4 m and it is covered with circular tiles of diameters 50 cm each as shown in Fig. 11.18. Find the area of floor that remains uncovered with tiles. (Use π = 3.14)

**Solution:**

Given, the floor of a room with dimensions 5 m × 4 m is covered with circular tiles of diameters 50 cm.

We have to find the area of the floor that remains uncovered with tiles.

Area of floor of a room = length × breadth

= 5 × 4

= 20 m²

Given, diameter of each circular tile = 50 cm

Number of tiles in each row = 5m/50cm

1 m = 100 cm

= 500/50

= 10

Number of tiles in each column = 4m/50cm

= 400/50

= 8

Total number of tiles in the floor = 10 × 8 = 80

Radius of tiles = 50/2 = 25 cm

r = 25/100

r = 0.25 m

Area of circle = πr²

Area of circular tile = (3.14)(0.25)²

= 0.19625 m²

Area of 80 tiles = 80(area of one tile)

= 80(0.196)

= 15.7 m²

Area of the floor that remains uncovered with the tiles = area of floor - area of 80 tiles

= 20 - 15.7

= 4.3 m²

Therefore, the area of the floor that remains uncovered with the tiles is 4.3 m².

**✦ Try This: **Floor of a room is of dimensions 6 m × 3 m and it is covered with circular tiles of diameters 20 cm each as shown in Fig. 11.18. Find the area of the floor that remains uncovered with tiles. (Use π = 3.14)

**☛ Also Check: **NCERT Solutions for Class 10 Maths Chapter 12

**NCERT Exemplar Class 10 Maths Exercise 11.4 Problem 11**

## Floor of a room is of dimensions 5 m × 4 m and it is covered with circular tiles of diameters 50 cm each as shown in Fig. 11.18. Find the area of floor that remains uncovered with tiles. (Use π = 3.14)

**Summary:**

Floor of a room is of dimensions 5 m × 4 m and it is covered with circular tiles of diameters 50 cm each as shown in Fig. 11.18. The area of floor that remains uncovered with tiles is 4.3 m²

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