The ratio of A and B is 5:3. If A is 15.5, what is the difference between A and B?
甲、乙两数的比是5：3，若甲数为15.5，则甲、乙两数的差是多少．
<gadget id="calculator">15.5 / 5</gadget>
<output>3.1</output>

<gadget id="calculator">3.1 * 3</gadget>
<output>9.3</output>

<gadget id="calculator">15.5 - 9.3</gadget>
<output>6.2</output>

<result>6.2</result>