Xiaohua's father works 4 days and takes 1 day off, and his mother works 3 days and takes one day off. On April 5, they both rest at the same time. At least how many days later will Xiaohua's parents rest at the same time?
小华的爸爸工作4天休息1天，妈妈工作3天休息一天，4月5日他们同时休息，至少再过多少天小华的爸爸妈妈又同时休息？
<gadget id="calculator">4 + 1</gadget>
<output>5</output>

<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<gadget id="calculator">5 * 4</gadget>
<output>20</output>

<result>20</result>