GMAT Problem Solving (PS) | The diagram above shows two wheels that drive a conveyor belt. The lar

If the larger wheel has a diameter of 40cm, the circumference is 40*pi.
Similarly, the smaller wheel(which has a diameter of 32 cm), will have 32*pi as circumference.

It has been said that the two wheels have the same number of rotations in a minute.
So, if the total number of revolutions the bigger wheel makes are r revolutions/minute, it would make 60r revolutions in an hour.
Let the revolution the smaller wheel makes in an hour be x.

40*pi*60*r = 32*pi*x

x =\( \frac{40*pi*60*r}{32*pi} \)
...

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