The football factory produced a batch of footballs in November, 30% of the total was produced in the first ten days, the first ten days (5/6) were produced in the middle ten days, and all the tasks were just completed in the second ten days. It is known that 90 more footballs were produced in the second half of the year than in the first ten days. How many footballs will be produced this month?
足球厂11月份生产一批足球，上旬生产了全部的30%，中旬生产的是上旬的(5/6)，下旬刚好全部完成任务．已知下旬比上旬多生产90个，这个月生产足球多少个？
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">5 / 6</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">(3/10) * (5/6)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (3/10) - (1/4) - (3/10)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">90 / (3/20)</gadget>
<output>600</output>

<result>600</result>