Pack a bunch of pencils into four boxes, one-fifth of them are put into box A, one-third are put into box B, the number of pencils put into box C is exactly three times the difference between the number of pencils in box A and box B, and D If there are 10 pencils in the box, how many pencils are there in total?
把一堆铅笔分装在四个盒子里，其中五分之一放入甲盒，三分之一放入乙盒，放入丙盒的铅笔正好是甲乙两盒铅笔数量差的三倍，丁盒放入10支铅笔，这堆铅笔共有多少支．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/3) - (1/5)</gadget>
<output>2/15 = around 0.133333</output>

<gadget id="calculator">(2/15) * 3</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (1/5) - (1/3) - (2/5)</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">10 / (1/15)</gadget>
<output>150</output>

<result>150</result>