Add basketball, volleyball and small football to the school sports room. Buy 4 basketballs, the number of basketballs bought is half of the volleyballs, and the number of small footballs bought is 7 times more than the total number of basketballs and volleyballs. How many small footballs did you buy?
学校体育室添置篮球、排球和小足球．买来篮球4个，买来的篮球的数量是排球的一半，买来的小足球的数量比篮球、排球总数的3倍多7个．买来多少个小足球？
<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">8 + 4</gadget>
<output>12</output>

<gadget id="calculator">12 * 3</gadget>
<output>36</output>

<gadget id="calculator">36 + 7</gadget>
<output>43</output>

<result>43</result>