Xiaojun’s father has to do several things before going to bed every day: it takes 3 minutes to prepare the clothes for the next day; 2 minutes to make the bed and get ready for sleep; 5 minutes to brush teeth and wash his face; 10 minutes; 10 minutes to read before going to bed. How many minutes can Xiaojun's father finish these things at least?
小军的爸爸每天睡觉前都要做几件事：准备第二天要穿的衣服要3分钟；整理床铺，准备睡觉要2分钟；刷牙、洗脸要5分钟；用温水泡脚并洗脚要10分钟；睡前阅读要10分钟．小军的爸爸最少用多少分钟能把这些事做完．
<gadget id="calculator">3 + 2 + 5 + 10</gadget>
<output>20</output>

<result>20</result>