Xiaoqiang reads a story book and reads the whole book every day (2/15). He has read a total of 84 pages in 7 days. How many pages does this book have?
小强读一本故事书，每天读全书的(2/15)，7天一共读了84页．这本书一共有多少页？
<gadget id="calculator">2 / 15</gadget>
<output>2/15 = around 0.133333</output>

<gadget id="calculator">84 / 7 / (2/15)</gadget>
<output>90</output>

<result>90</result>