# Floor Area

The length of canvas 75 cm wide required to build a conical tent of height 14 m and the floor area 346.5 m² is:

- 490 m
- 860 m
- 665 m
- 770 m

**Answer: (4) 770 cm**

**Explanation:-
**Let the length of canvas be X m.

The floor area of conical tent = 346.5

Formula –

Floor area of the conical tent = pai x r^2

Then, pai x r^2 = 346.5

r^2 = 346.5 x 7/22

r^2 = 110.25

Square root on both side,

r = 10.5 cm

Then, the slant height of the canvas = (10.5^{2} + 14^{2})^{1/2
} = (306.5)^{1/2}

Area of the canvas = Curved surface area of the conical tent

Then, 75 x X /100 = pai x r x 17.5

3 X /4 = 22 x 10.5 x 17.5/7

X = 7.7 m

X = 770 cm (1m = 100 cm)

Hence, the answer is (4) 770 cm.