Xiao Ming has a total of 56 story books and technology books, among which technology books account for (3/8) of all the books. How many technical books did you buy back?
小明有故事书和科技书共56本，其中科技书占全部书的(3/8)，后来小明又买回了一些科技书，这样科技书就占全部书的(2/3)，小明又买回科技书几本？
<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">1 - (3/8)</gadget>
<output>5/8 = around 0.625</output>

<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 - (2/3)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(5/8) / (1/3)</gadget>
<output>15/8 = around 1.875</output>

<gadget id="calculator">56 * (15/8)</gadget>
<output>105</output>

<gadget id="calculator">105 - 56</gadget>
<output>49</output>

<result>49</result>