Aunt Zhang’s house has two bookcases. The books on bookcase A belong to bookcase B (4/5). After taking 10 books from bookcase A and putting them in bookcase B, the books on bookcase A belong to bookcase B (5/7). ． How many books were there on the A bookcase?
张阿姨家有两个书柜，甲书柜上的书是乙书柜的(4/5)，从甲书柜上拿10本放到乙书柜后，甲书柜上的书是乙书柜的(5/7)．甲书柜上原来有多少本书？
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 + (4/5)</gadget>
<output>9/5 = around 1.8</output>

<gadget id="calculator">(4/5) / (9/5)</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">5 / 7</gadget>
<output>5/7 = around 0.714286</output>

<gadget id="calculator">1 + (5/7)</gadget>
<output>12/7 = around 1.714286</output>

<gadget id="calculator">(5/7) / (12/7)</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">(4/9) - (5/12)</gadget>
<output>1/36 = around 0.027778</output>

<gadget id="calculator">10 / (1/36)</gadget>
<output>360</output>

<gadget id="calculator">360 * (4/9)</gadget>
<output>160</output>

<result>160</result>