In making 1000 revolutions, a wheel covers 88 km. The diameter of the wheel is
Distance the wheel travels = 88 km = 88000 m
In 1 revolution wheel travels 2πr distance
No. of revolutions a wheel makes = 
No. of revolutions a wheel makes = 1000
= 14 m
Radius of wheel = 14 m
Diameter of wheel = 2 × 14 m = 28 m
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