In an alloy of copper and tin, the ratio of copper to tin is 9:5. It is known that copper is 800 grams heavier than tin. How many grams is this alloy?
一块铜和锡的合金中，铜与锡的比是9：5，已知铜比锡重800克，这块合金有多少克．
<gadget id="calculator">9 - 5</gadget>
<output>4</output>

<gadget id="calculator">800 / 4</gadget>
<output>200</output>

<gadget id="calculator">9 + 5</gadget>
<output>14</output>

<gadget id="calculator">200 * 14</gadget>
<output>2_800</output>

<result>2_800</result>