A certain type of telephone will charge 0.3 yuan immediately. If it exceeds 3 minutes, an additional 0.25 yuan will be charged for each minute (less than 1 minute is counted as 1 minute). Xiao Ming makes a call and pays 1.8 yuan. How much is the average call fee per minute?
某种电话拨通即收0.3元，如果超过3分钟，每超过1分钟(不足1分钟按1分钟计算)再加收0.25元．小明拨打一次，付费1.8元，平均每分钟电话费是多少元？
<gadget id="calculator">1.8 - 0.3</gadget>
<output>1.5</output>

<gadget id="calculator">1.5 / 0.25</gadget>
<output>6</output>

<gadget id="calculator">6 + 3</gadget>
<output>9</output>

<gadget id="calculator">1.8 / 9</gadget>
<output>0.2</output>

<result>0.2</result>