A stationery store has 5 brands of ballpoint pens. Each ballpoint pen has 3 colors of red, green and purple, and each color has 3 models. How many styles of ballpoint pens does this stationery store have for students to choose from?
某文具店有5种牌子的圆珠笔，每种圆珠笔有红、绿、紫3种颜色，每种颜色又有3种型号，这家文具店共有多少种款式的圆珠笔可供学生选择．
<gadget id="calculator">5 * 3 * 3</gadget>
<output>45</output>

<result>45</result>