If a*(1/6)=b/(3/5)=c/(6/7), and a, b, c are all non-zero natural numbers. So what is the minimum value of the sum of a+b+c?
如果a*(1/6)=b/(3/5)=c/(6/7)，并且a，b，c都是不为零的自然数．那么a+b+c和的最小值是多少．
<gadget id="calculator">70 + 10 + 7</gadget>
<output>87</output>

<result>87</result>