Classes A and B each have 200 books. After A gives B how many copies, B has 50% more copies than A.
甲乙两班各有200本图书．甲给乙多少本后，乙的本数比甲多50%．
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">200 * (1/2)</gadget>
<output>100</output>

<gadget id="calculator">100 - 200</gadget>
<output>-100</output>

<gadget id="calculator">200 + (-100)</gadget>
<output>100</output>

<gadget id="calculator">1 + (1/2) + 1</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">100 / (5/2)</gadget>
<output>40</output>

<result>40</result>