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प्रश्न
The cost of fencing a circular race course at the rate of ₹ 8 per metre is ₹ 2112. Find the diameter of the race course
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उत्तर
Cost of fencing the circumference = ₹ 2112
Cost of fencing one meter = ₹ 8
∴ Circumference of the circle = `2112/8` = 264 m
πd = 264 m
`22/7 xx "d"` = 264
d = `(264 xx 7)/22`
= 12 × 7 m
= 84 m
∴ Diameter of the race cource = 84 m
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