Li Ming wrote 75 brush characters in 3 days. According to this calculation, how many brush characters can he write in a week?
李明3天写了75个毛笔字，照这样计算，他一个星期能写几个毛笔字﹖
<gadget id="calculator">75 / 3</gadget>
<output>25</output>

<gadget id="calculator">25 * 7</gadget>
<output>175</output>

<result>175</result>