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A wheel of a car covers a distance of 3520 cm in 20 rotations. Find the radius of the wheel?

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#### Solution

Distance covered by circular wheel in 20 rotation = 3520 cm

∴ Distance covered in rotation = `3520/20 "cm"` = 176 cm

∴ Circumference of the wheel = 176 cm

∴ 2πr = 176

`2 xx (-2)/6 xx "r"` = 176

r = `(176 xx 7)/(2 xx 22)`

r = 28 cm

Radius of the wheel = 28 cm

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