The product of two inner terms of a ratio is (1/5), one of the outer terms is 4, and what is the other outer term.
一个比例两个内项的积是(1/5)，其中一个外项是4，另一个外项是多少．
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/5) / 4</gadget>
<output>1/20 = around 0.05</output>

<result>1/20 = around 0.05</result>