It is known that (1/4)x=(1/5), then 5x=how much.
已知(1/4)x=(1/5)，那么5x=多少．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/5) / (1/4)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">5 * (4/5)</gadget>
<output>4</output>

<result>4</result>