In a ratio, the product of two outer terms is (3/5), one inner term is 3, and the other inner term is what.
在一个比例中，两个外项的积是(3/5)，一个内项是3，另一个内项是多少．
<gadget id="calculator">3 / 5</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(3/5) / 3</gadget>
<output>1/5 = around 0.2</output>

<result>1/5 = around 0.2</result>