It is known that it takes A alone to complete a project in 30 days, B alone in 45 days, and C in 90 days alone. Now A, B, and C are working together to complete the project. During this process, A rested for 2 days, B rested for 3 days, and C did not rest, and finally completed the project. Q: How many days was the project completed from the start?
已知甲单独完成一项工程需30天，乙单独完成需45天，丙单独完成需90天，现由甲、乙、丙三人合作完成此项工程．在此过程中，甲休息了2天，乙休息了3天，丙没有休息，最后把工程完成了．问：这项工程从开始算起是第几天完成的？
<gadget id="calculator">1 / 30</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">1 / 90</gadget>
<output>1/90 = around 0.011111</output>

<gadget id="calculator">(1/90) * 3</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">1 - (1/30) - (1/30)</gadget>
<output>14/15 = around 0.933333</output>

<gadget id="calculator">1 / 45</gadget>
<output>1/45 = around 0.022222</output>

<gadget id="calculator">(1/30) + (1/45) + (1/90)</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">(14/15) / (1/15)</gadget>
<output>14</output>

<gadget id="calculator">14 + 3</gadget>
<output>17</output>

<result>17</result>