The school bought 315 undergraduate textbooks and lent them to fifth and sixth graders at a ratio of 3:4, so how many books are borrowed less in fifth grade than in sixth grade?
学校买来315本科普读物，按3：4的比借给五、六年级的同学，那么五年级比六年级少借多少本？
<gadget id="calculator">3 + 4</gadget>
<output>7</output>

<gadget id="calculator">315 / 7</gadget>
<output>45</output>

<gadget id="calculator">4 - 3</gadget>
<output>1</output>

<gadget id="calculator">45 * 1</gadget>
<output>45</output>

<result>45</result>