Question

A path of width 3.5m runs around a semi-circular grassy plot whose perimeter is 72m. find the area of the path.(Use π=22/7)

Answer 1

Answer:

173.25m²

Solution :-

πr + 2r = Perimeter of circle

π (r + 2r) = 72

$r \: = \frac{72}{\pi + 2} = \frac{72}{ \frac{22}{7} + \frac{2}{1} } \\ \\ = \frac{72}{ \frac{22 + 14}{7} } = \frac{72}{ \frac{36}{7} } \\ \\ = \frac{72}{36} \times 7 \\ \\ = 14$

Outer Radius

= 14 + 3.5

= 17.5 m

Area of path

$\frac{1}{2}\pi( {r}^{2} - {r}^{2} ) \\ \\ = \geqslant \frac{1}{2} \times \frac{22}{7} |(17.5) {}^{2} \: - (14) {}^{2} | \\ \\ = \geqslant \frac{1}{2} \times \frac{22}{7} \times 31.5 \times 35 \\ \\ = \geqslant \frac{11 \times 31.5}{2} \\ \\ = \geqslant 173.25 {m}^{2}$

Answer 2

Answer:

your answer is 173.25

Step-by-step explanation:

hope the answer will help you