Class 5 and Class 1 bought 20 garlands and 20 colored balls to decorate the classroom. It is known that the colored balls are 3.5 yuan each, and the garland and the colored balls are 100 yuan. How much is each wreath? (Solution of column equation)
五1班同学买来花环和彩球各20个布置教室．已知彩球每个3.5元，花环和彩球共用去100元．每个花环多少元？(列方程解)
<gadget id="calculator">3.5 * 20</gadget>
<output>70</output>

<gadget id="calculator">100 - 70</gadget>
<output>30</output>

<gadget id="calculator">30 / 20</gadget>
<output>3/2 = around 1.5</output>

<result>3/2 = around 1.5</result>