The sum of two numbers is greater than one of them (4/9) and greater than the other (2/9), what is the sum of these two numbers
两个数的和比其中一个数大(4/9)，比另一个大(2/9)，这两个数的和是多少
<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>2/3 = around 0.666667</output>

<result>2/3 = around 0.666667</result>