40% of a number is 80, what is 75% of it.
一个数的40%是80，它的75%是多少．
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">80 / (2/5)</gadget>
<output>200</output>

<gadget id="calculator">75 / 100</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">200 * (3/4)</gadget>
<output>150</output>

<result>150</result>