The ratio of A, B, and C is 4:3:2, and the average of these three numbers is 4.5. So how much less is the number C than the number A?
甲、乙、丙三个数的比是4：3：2，这三个数的平均数是4.5．那么丙数比甲数少多少．
<gadget id="calculator">4 + 3 + 2</gadget>
<output>9</output>

<gadget id="calculator">4 / 9</gadget>
<output>4/9 = around 0.444444</output>

<gadget id="calculator">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">(4/9) - (2/9)</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">4.5 * 3 * (2/9)</gadget>
<output>3</output>

<result>3</result>