(13/15)*(5/9)+(4/15)*(13/9).
(13/15)*(5/9)+(4/15)*(13/9)．
<gadget id="calculator">13 / 15</gadget>
<output>13/15 = around 0.866667</output>

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

<gadget id="calculator">(13/15) * (5/9)</gadget>
<output>13/27 = around 0.481481</output>

<gadget id="calculator">4 / 15</gadget>
<output>4/15 = around 0.266667</output>

<gadget id="calculator">13 / 9</gadget>
<output>13/9 = around 1.444444</output>

<gadget id="calculator">(4/15) * (13/9)</gadget>
<output>52/135 = around 0.385185</output>

<gadget id="calculator">(13/27) + (52/135)</gadget>
<output>13/15 = around 0.866667</output>

<result>13/15 = around 0.866667</result>