The ratio of the price of the table to the price of the chair is 3:1. The total cost of buying the chair and the table is 2680 yuan. How much is the cost of the chair?
桌子的价钱和椅子价钱的比是3：1，买椅子和桌子共花2680元，椅子花去多少元？
<gadget id="calculator">1 + 3</gadget>
<output>4</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">2_680 * (1/4)</gadget>
<output>670</output>

<result>670</result>