A's number is 137, B's number is 5 times of A's number, what is the difference between A's and B's numbers?
甲数是137，乙数是甲数的5倍，甲乙两数相差多少？
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">137 * 4</gadget>
<output>548</output>

<result>548</result>