Pingping's mother works on the eighth floor. One day, Pingping went to find her mother. It took her 40 seconds to walk from the first floor to the fifth floor. Calculated at this speed, how many seconds will she have to walk at least to reach her mother's office.
萍萍的妈妈在八楼办公．有一天，萍萍去找妈妈，她从一楼走到五楼，用了40秒．照这样的速度计算，她至少要再走多少秒才能到达她妈妈的办公室．
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">40 / 4</gadget>
<output>10</output>

<gadget id="calculator">8 - 5</gadget>
<output>3</output>

<gadget id="calculator">10 * 3</gadget>
<output>30</output>

<result>30</result>