The ratio of the number of people participating in the mathematics, physics and chemistry teams in the third grade is 6:5:4. There are 135 people in the three groups. How many people are there in the physics group?
初三年级参加数、理、化小组的人数比是6：5：4．三个组共有135人，问参加物理小组有多少人．
<gadget id="calculator">6 + 5 + 4</gadget>
<output>15</output>

<gadget id="calculator">5 / 15</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">135 * (1/3)</gadget>
<output>45</output>

<result>45</result>