((1/15)+(2/17))*15*17.
((1/15)+(2/17))*15*17．
<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">2 / 17</gadget>
<output>2/17 = around 0.117647</output>

<gadget id="calculator">(1/15) + (2/17)</gadget>
<output>47/255 = around 0.184314</output>

<gadget id="calculator">(47/255) * 15 * 17</gadget>
<output>47</output>

<result>47</result>