Both A and B are natural numbers, the decomposed prime factor A=2*5*C, B=3*5*C, if the greatest common factor of A and B is 30, what is C=?
A和B都是自然数，分解质因数A=2*5*C，B=3*5*C，如果A和B的最大公因数是30，C=多少．
<gadget id="calculator">30 / 5</gadget>
<output>6</output>

<result>6</result>