The area of a trapezoid is 30 square centimeters, the ratio of the length of the upper base to the lower base is 2:3, and the height is 6 cm, what is the length of the upper base in cm
一个梯形的面积是30平方厘米，上底与下底长度比是2：3，高是6厘米，则上底长为多少厘米
<gadget id="calculator">2 / 6</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">30 * (1/3)</gadget>
<output>10</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">10 * (2/5)</gadget>
<output>4</output>

<result>4</result>