(5/(1*2))+(5/(2*3))+(5/(3*4))+(5/(4*5))+(5/(6*7))+ (5/(7*8))+(5/(8*9))+(5/(9*10))=how much.
(5/(1*2))+(5/(2*3))+(5/(3*4))+(5/(4*5))+(5/(6*7))+(5/(7*8))+(5/(8*9))+(5/(9*10))=多少．
<gadget id="calculator">9 / 10</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">5 * (9/10)</gadget>
<output>9/2 = around 4.5</output>

<result>9/2 = around 4.5</result>