The average of A and B is 63, the ratio of A and B is 5:4, what is the difference between A and B?
甲、乙两数的平均数是63，甲数与乙数的比为5：4，甲乙两数相差是多少．
<gadget id="calculator">5 + 4</gadget>
<output>9</output>

<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

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

<gadget id="calculator">(5/9) - (4/9)</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">63 * 2 * (1/9)</gadget>
<output>14</output>

<result>14</result>