There is a piece of bronze, which is made of three metals: copper, tin and zinc. Among them, copper accounts for (17/25) of the total weight, tin accounts for (1/5) of the total weight, and what percentage of zinc accounts for the total weight?
有一块青铜，是由铜、锡和锌三种金属熔合而成的．其中铜占总重量的(17/25)，锡占总重量的(1/5)，锌占总重量的几分之几？
<gadget id="calculator">17 / 25</gadget>
<output>17/25 = around 0.68</output>

<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (17/25) - (1/5)</gadget>
<output>3/25 = around 0.12</output>

<result>3/25 = around 0.12</result>