It is known that 2A+3=15, so how much is 4A+6=.
已知2A+3=15，那么4A+6=多少．
<gadget id="calculator">4 * 6</gadget>
<output>24</output>

<gadget id="calculator">24 + 6</gadget>
<output>30</output>

<result>30</result>