Teams A, B, and C cooperate on a project. A and B cooperate to complete a project in 10 days, B and C cooperate in 12 days, and A and C cooperate in 15 days. Now let A and B. C cooperates for 3 days, and the rest is done by Team A alone. How many days does Team A have to do?
甲、乙、丙三队合作一项工程，甲、乙合作要10天完成，乙、丙合作要12天完成，甲、丙合作要15天完成．现在先由甲、乙．丙合作3天，余下的由甲队单独完成，甲队还要做多少天？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">(1/10) + (1/12) + (1/15)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/4) / 2</gadget>
<output>1/8 = around 0.125</output>

<gadget id="calculator">(1/8) * 3</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">(1/8) - (1/12)</gadget>
<output>1/24 = around 0.041667</output>

<gadget id="calculator">(5/8) / (1/24)</gadget>
<output>15</output>

<result>15</result>