50 tons increased by (1/4) and then decreased by (1/4) is how many tons.
50吨增加(1/4)后再减少(1/4)是多少吨．
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 + (1/4)</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">50 * (5/4) * (3/4)</gadget>
<output>375/8 = around 46.875</output>

<result>375/8 = around 46.875</result>