Processing a batch of parts can be completed in 15 days by cooperation between A and B. Now A will do it for 10 days first, and then B will do it for 12 days. The rest (1/4) of this batch of parts has not been completed. It is known that A is more than B every day. If 5 parts are processed less, find the number of this batch of parts.
加工一批零件，甲、乙合作15天可以完成，现在由甲先做10天，然后乙再做12天，还剩下这批零件的(1/4)没有完成，已知甲每天比乙少加工5个零件，求这批零件的个数．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">(1/15) * 10</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 - (1/4) - (2/3)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/12) / 2</gadget>
<output>1/24 = around 0.041667</output>

<gadget id="calculator">(1/15) - (1/24)</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">(1/24) - (1/40)</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">5 / (1/60)</gadget>
<output>300</output>

<result>300</result>