When multiplying two numbers, if one factor increases by 1.8, the product increases by 7.2; if the other factor subtracts 3, the product decreases by 4.5. What is the product of multiplying the two numbers together?
两个数相乘，如果一个因数增加1.8，积就增加7.2；如果另一个因数减去3，积就减少4.5．原来两数相乘的积是多少．
<gadget id="calculator">7.2 / 1.8</gadget>
<output>4</output>

<gadget id="calculator">4.5 / 3</gadget>
<output>1.5</output>

<gadget id="calculator">4 * 1.5</gadget>
<output>6</output>

<result>6</result>