Question

the inner circumference of a circular track is 220m. the track is 7m wide everywhere. calculate the cost of fencing along the outer circle at the rate of Rs 2 per m.

Answer 1

Step-by-step explanation:

circumference of inner circular track = 220 m

2πr = 220

$2\pi \: r = 220 \\ r = \frac{220 \times 7}{2 \times 22} \\ r = 5 \times 7 = 35$

width of track is 7 m

therefore radius of outer circle = 35 + 7 = 42 m

circumference of outer circle

$2\pi \: r \\ = 2 \times \frac{22}{7} \times 42 \\ = 2 \times 22 \times 6 \\ = 44 \times 6 \\ = 264 \: m$

cost of fencing @Rs. 2 per meter

= 264 × 2

= 528

total cost of fencing = Rs. 528

hope you get your answer