There are 50-100 students who participated in the mathematics competition in the sixth grade of the school. Those who won the first prize accounted for (1/7) of the total number of participants, and those who won the second prize accounted for (1/6) of the total number of participants. Those who are waiting for the prize account for (1/3) of the total number of participants, so how many people did not win the prize?
学校六年级参加数学竞赛的同学有50-100人，成绩得一等奖的恰好占参赛总人数的(1/7)，得二等奖的占参赛总人数的(1/6)，得三等奖的占参赛总人数的(1/3)，那么没获奖的有多少人？
<gadget id="calculator">1 / 7</gadget>
<output>1/7 = around 0.142857</output>

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

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

<gadget id="calculator">1 - (1/7) - (1/6) - (1/3)</gadget>
<output>5/14 = around 0.357143</output>

<gadget id="calculator">84 * (5/14)</gadget>
<output>30</output>

<result>30</result>