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Question
A wheel has a diameter of 84 cm. Find how many completer revolutions must it make to cover 3.168 km.
Solution
The diameter of the wheel = 84 cm
Thus, the radius of the wheel = 42 cm
Circumference of the wheel = 2 x `22/7` x 42 = 264 cm
In 264 cm, the wheel is covering one revolution.
Thus, in 3.168 km = 3.168 x 100000 cm, number of revolutions
covered by the wheel = `3.168/264 xx 100000` = 1200.
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