Cut a circle with a diameter of 15 cm into two semicircles along one diameter, what is the circumference of each semicircle in cm?
把一个直径是15厘米的圆，沿一条直径剪成两个半圆，每个半圆的周长是多少厘米．
<gadget id="calculator">15 / 2</gadget>
<output>15/2 = around 7.5</output>

<gadget id="calculator">3.14 * (15/2)</gadget>
<output>23.55</output>

<gadget id="calculator">23.55 + 15</gadget>
<output>38.55</output>

<result>38.55</result>