Ou Zebra has 190 jellies, Ou Ou has 30 chocolates, each time Ao Zebra gives O Ou 5 jellies, and Ou Ou gives O Ou 1 chocolate. Then, to make the amount of jelly in O'Zebra's hand be 9 times the amount of chocolate in O'Ou's hand, how many times does it have to go through such exchanges?
奥斑马有190个果冻，欧欧有30个巧克力，每次奥斑马给欧欧5个果冻，而欧欧给奥斑马1个巧克力．那么，要使奥斑马手中的果冻数量是欧欧手中巧克力数量的9倍，要经过这样的交换多少次．
<gadget id="calculator">9 * 30</gadget>
<output>270</output>

<gadget id="calculator">270 - 190</gadget>
<output>80</output>

<gadget id="calculator">9 - 5</gadget>
<output>4</output>

<gadget id="calculator">80 / 4</gadget>
<output>20</output>

<result>20</result>