Xiao Ming walked from home to school for 20 minutes, and his speed increased by (1/4) when he came back. How many minutes did he take when he came back?
小明从家去学校走了20分钟，回来时速度提高(1/4)，回来时用了多少分钟．
<gadget id="calculator">1 / 20</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 + (1/4)</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">(1/20) * (5/4)</gadget>
<output>1/16 = around 0.0625</output>

<gadget id="calculator">1 / (1/16)</gadget>
<output>16</output>

<result>16</result>