(2/5) of the number A is equal to (1/6) of the number B. It is known that the number A is 28 smaller than the number B. Find the number A.
甲数的(2/5)与乙数的(1/6)相等，已知甲数比乙数小28，求甲数．
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(1/6) / (2/5)</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">1 - (5/12)</gadget>
<output>7/12 = around 0.583333</output>

<gadget id="calculator">28 / (7/12)</gadget>
<output>48</output>

<gadget id="calculator">48 - 28</gadget>
<output>20</output>

<result>20</result>