Experimental Primary School has a batch of extracurricular books distributed to students in grades 4, 5, and 6. 30% of the books are assigned to grade 4, and the rest are distributed to grades 5 and 6 at a ratio of 1:5. It is known that there are 140 books in the fifth grade, how many books are there in this batch of extracurricular reading materials?
实验小学有一批课外书分给四、五、六年级的学生阅读，四年级分到这批书的30%，其余的按1：5的比分给五、六年级．已知五年级分到140本，这批课外读物一共多少本？
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">1 + 5</gadget>
<output>6</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(7/10) * (1/6)</gadget>
<output>7/60 = around 0.116667</output>

<gadget id="calculator">140 / (7/60)</gadget>
<output>1_200</output>

<result>1_200</result>