During the summer vacation, Xiaojie got a sum of pocket money for helping his mother with housework. At the beginning of school, he spent 2/5 of the total pocket money on school supplies and 3/8 of the total pocket money on extracurricular reading materials. The rest of the pocket money was donated to the children in the disaster area. The disaster area donated 90 yuan, so how much is his pocket money in total?
暑假期间，小杰帮妈妈做家务得到了一笔零用钱．开学时，他买学习用品花了总零用钱的(2/5)，买课外读物花了总零用钱的(3/8)，剩下的零用钱全部捐给灾区的小朋友，如果小杰向灾区捐了90元，那么他的零用钱一共有多少元？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">1 - (2/5) - (3/8)</gadget>
<output>9/40 = around 0.225</output>

<gadget id="calculator">90 / (9/40)</gadget>
<output>400</output>

<result>400</result>