To build a section of road, team A will complete the repair in 20 days alone, and team B will complete the repair in 15 days. Now, team A will repair it alone for 5 days, and team B will join in and work together with team A for 3 days. If there is an emergency, the rest of the project can only be repaired by Team B alone. How many days will Team B need to complete the repairs? (Arithmetic solution)
修一段路，甲队单独修要20天完成，乙队单独修要15天完成，现在先由甲队单独修5天后，乙队加入进来与甲队一起合修了3天，这时甲队因有事披外调，余下的工程只能由乙队单独修，请问乙队还要修多少天才能完成？(算术方法解答)
<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">(1/20) * 5</gadget>
<output>1/4 = around 0.25</output>

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

<gadget id="calculator">(1/20) + (1/15)</gadget>
<output>7/60 = around 0.116667</output>

<gadget id="calculator">(7/60) * 3</gadget>
<output>7/20 = around 0.35</output>

<gadget id="calculator">(1/4) + (7/20)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">1 - (3/5)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(2/5) / (1/15)</gadget>
<output>6</output>

<result>6</result>