There are 150 students in the first grade this year, an increase of (1/2) from last year. How many people were there last year?
一年级今年有150人，比去年增加了(1/2)，去年有多少人．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 + (1/2)</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">150 / (3/2)</gadget>
<output>100</output>

<result>100</result>