Teacher Chen buys 5 copies of the same book for 70 yuan. If the price of the book is reduced to half of the original price, how many copies of this book can be bought for 350 yuan.
陈老师70元买5本同样的书，如果书的价格降到原来的一半，那么350元可以买多少本这样的书．
<gadget id="calculator">70 / 5 / 2</gadget>
<output>7</output>

<gadget id="calculator">350 / 7</gadget>
<output>50</output>

<result>50</result>