A bottle of ink is 4 yuan, and an exercise book is 80 cents. How many exercise books can be bought for the price of a bottle of ink.
一瓶墨水4元钱，一个练习本8角钱，买一瓶墨水的钱数可以买多少个练习本．
<gadget id="calculator">10 / 8</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">4 * (5/4)</gadget>
<output>5</output>

<result>5</result>