In the sixth grade mathematics interest group activity, 75% of the students who participated were those who did not participate. Later, 48 people participated. At this time, the number of students who participated was 1.5 times that of those who did not participate. How many people are there in the sixth grade?
六年级数学兴趣小组活动时，参加的同学是未参加的75%，后来又有48人参加，这时参加的同学是未参加的1.5倍，六年级一共有多少人？
<gadget id="calculator">6 / 21</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">48 / (2/7)</gadget>
<output>168</output>

<result>168</result>