The number of A is (2/3) of the number of B. If the number of B increases by 20, the number of B is 4 times of the number of A. What is the number of A?
甲数是乙数的(2/3)，如果乙数增加20，则乙数是甲数的4倍，甲数是多少？
<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">4 - (3/2)</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">20 / (5/2)</gadget>
<output>8</output>

<result>8</result>