Solve the equation: (4800/(x))=(5000/(x+20)).
解方程：(4800/(x))=(5000/(x+20))．
<gadget id="calculator">4_800 * 20</gadget>
<output>96_000</output>

<gadget id="calculator">5_000 - 4_800</gadget>
<output>200</output>

<gadget id="calculator">96_000 / 200</gadget>
<output>480</output>

<result>480</result>