book, I read it in 7 days with a smile, how much do I read this book on average every day
一本书，笑笑7天看完，平均每天看这本书的多少
<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<result>1/7 = around 0.142857</result>