There are two kinds of ballpoint pens in the small school store. The money that Xiao Ming brings is just enough to buy 4 sticks at a unit price of 1.5 yuan. If he wants to buy all of them at a unit price of 2 yuan, how many sticks can he buy? (Solve with ratio)
学校小商店有两种圆珠笔．小明带的钱刚好可以买4枝单价是1.5元的，如果他想都买单价是2元的，可以买多少枝？(用比例解)
<gadget id="calculator">1.5 * 4</gadget>
<output>6</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<result>3</result>