If the product of two outer terms is the smallest composite number, one of the inner terms is (4/5), what is the other inner term.
如果两个外项的积是最小的合数，其中一个内项是(4/5)，另一个内项是多少．
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

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

<result>5</result>