The two bookstores A and B opened by Xiaoming’s father sell the same number of books of the same kind. 70% of the books in bookstore A are sold out, and all the books in bookstore B are sold out. How many.
小明爸爸开的甲乙两个书店出售相同数量的同一种书，甲书店的书卖出了70%，乙书店的书全部卖完，如果把两个书店合起来算，卖出的书占总数的多少．
<gadget id="calculator">70 / 100</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">1 * (7/10)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">(7/10) + 1</gadget>
<output>17/10 = around 1.7</output>

<gadget id="calculator">1 + 1</gadget>
<output>2</output>

<gadget id="calculator">(17/10) / 2</gadget>
<output>17/20 = around 0.85</output>

<result>17/20 = around 0.85</result>