A shoe store comes in with 600 pairs of leather shoes. (1/5) of the total amount sold in the first week, and (3/8) of the total amount sold in the second week. How many pairs are left unsold?
某鞋店进来皮鞋600双．第一周卖出总数的(1/5)，第二周卖出总数的(3/8)．还剩下多少双没有卖出去？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

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

<gadget id="calculator">1 - (1/5) - (3/8)</gadget>
<output>17/40 = around 0.425</output>

<gadget id="calculator">600 * (17/40)</gadget>
<output>255</output>

<result>255</result>