The number of A is 60, the number of B is (2/5) of the number of A, what is the number of B
甲数是60，乙数是甲数的(2/5)，乙数是多少
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">60 * (2/5)</gadget>
<output>24</output>

<result>24</result>