The product of two factors is 3.12. If one factor remains unchanged and the other factor is multiplied by 5, what is the product?
两个因数的积是3.12，如果一个因数不变，另一个因数扩大5倍，积应是多少．
<gadget id="calculator">3.12 * 5</gadget>
<output>15.6</output>

<result>15.6</result>