The school has 80 basketballs and volleyballs. There are 4 more basketballs than volleyballs. How many basketballs are there?
学校有篮球和排球共80个，篮球比排球多4个，篮球有多少个．
<gadget id="calculator">80 + 4</gadget>
<output>84</output>

<gadget id="calculator">84 / 2</gadget>
<output>42</output>

<result>42</result>