For the convenience of calculation, sometimes some fractions can be rewritten into the form of adding or subtracting two or more fractions, such as: (3/10)=(1/5)+(1/10)=(1/ 2)-(1/5), (2/21)=(1/14)+(1/42)=(2/3)-(4/7). Please use your ingenuity to calculate: (1/3)-(2/15)+(3/35)-(4/63)+(5/99)-(6/143)=how much.
为了计算方便，有时可把一些分数改写成二个或二个以上的分数相加或相减的形式，如：(3/10)=(1/5)+(1/10)=(1/2)-(1/5)，(2/21)=(1/14)+(1/42)=(2/3)-(4/7)．请发挥你的聪明才智计算：(1/3)-(2/15)+(3/35)-(4/63)+(5/99)-(6/143)=多少．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">2 / 15</gadget>
<output>2/15 = around 0.133333</output>

<gadget id="calculator">(1/3) - (2/15)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">3 / 35</gadget>
<output>3/35 = around 0.085714</output>

<gadget id="calculator">4 / 63</gadget>
<output>4/63 = around 0.063492</output>

<gadget id="calculator">(3/35) - (4/63)</gadget>
<output>1/45 = around 0.022222</output>

<gadget id="calculator">5 / 99</gadget>
<output>5/99 = around 0.050505</output>

<gadget id="calculator">6 / 143</gadget>
<output>6/143 = around 0.041958</output>

<gadget id="calculator">(5/99) - (6/143)</gadget>
<output>1/117 = around 0.008547</output>

<gadget id="calculator">(1/5) + (1/45) + (1/117)</gadget>
<output>3/13 = around 0.230769</output>

<result>3/13 = around 0.230769</result>