Boris Biker entered the Tour de Transylvania with an unusual bicycle whose back wheel is larger than the front. The radius of the back wheel is 40 cm, and the radius of the front wheel is 30 cm. On the first stage of the race the smaller wheel made 120000 revolutions.
How many revolutions did the large wheel make?
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90000
90000\pi
160000
\frac{160000}{\pi}
120000
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