The school purchased 16 basketballs this year, and 4 volleyballs were 1.5 times less than basketballs. How many volleyballs did the school buy this year?
学校今年购进篮球16个，购进的排球比篮球的1.5倍少4个．学校今年购进排球多少个？
<gadget id="calculator">16 * 1.5</gadget>
<output>24</output>

<gadget id="calculator">24 - 4</gadget>
<output>20</output>

<result>20</result>