The number A is 20 more than the number B, and the number B is 20% less than the number A, what is the number A, and what is the correct formula
甲数比乙数多20，乙数比甲数少20%，求甲数是多少，正确列式是多少
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">20 / (1/5)</gadget>
<output>100</output>

<result>100</result>