A rectangle with a length of 5 cm and a width of 3 cm is enlarged by 3:1, how many times the area of the obtained figure is the original.
一个长5cm、宽3cm的长方形按3：1放大，得到的图形的面积是原来的多少倍．
<gadget id="calculator">3 * 5</gadget>
<output>15</output>

<gadget id="calculator">3 / 15</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">5 * 3 * 3 * (1/5)</gadget>
<output>9</output>

<result>9</result>