Xiao Ming has 9 pencils, and Xiao Hua has 15 pencils. If Xiao Hua has three times as many pencils as Xiao Ming, how many pencils should Xiao Ming give Xiao Hua?
小明有9支铅笔，小华有15支铅笔，要使小华的铅笔支数是小明的3倍，小明应该给小华多少支铅笔．
<gadget id="calculator">9 + 15</gadget>
<output>24</output>

<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<gadget id="calculator">24 / 4</gadget>
<output>6</output>

<gadget id="calculator">9 - 6</gadget>
<output>3</output>

<result>3</result>