The number A is (9/5). The product of A and B is 20 more than the number B. What is the product of A and B?
甲数是(9/5)，甲、乙两数的积比乙数多20，甲乙两数的积是多少．
<gadget id="calculator">9 / 5</gadget>
<output>9/5 = around 1.8</output>

<gadget id="calculator">(9/5) - 1</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">20 / (4/5)</gadget>
<output>25</output>

<gadget id="calculator">25 * (9/5)</gadget>
<output>45</output>

<result>45</result>