In the physical education class of Zhenhai Yale School, the students practiced playing basketball. The teacher gave half of all the basketballs to the male students, and the remaining half to the female students. Now the teacher still has 4 basketballs in his hand. How many basketballs did the teacher have?
镇海雅乐学校的体育课上，同学们练习打篮球．老师将所有篮球的一半给了男同学，剩下的一半分给了女同学，现在老师手里还有4个篮球．老师原来有多少个篮球．
<gadget id="calculator">4 * 2 * 2</gadget>
<output>16</output>

<result>16</result>