The number A is more than the number B (1/3), if the number A is 20, what is the formula of the B number
甲数比乙数多(1/3)，如果甲数是20，求乙数列式子为多少
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 + (1/3)</gadget>
<output>4/3 = around 1.333333</output>

<gadget id="calculator">20 / (4/3)</gadget>
<output>15</output>

<result>15</result>