Xiao Fangu has read the whole book (2/5), and the read is 30 pages less than the rest. How many pages does this book have?
小芳度一本书，已经读了全书的(2/5)，已读的比剩下的少30页，这本书共有多少页？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5) - (2/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">30 / (1/5)</gadget>
<output>150</output>

<result>150</result>