Sixth grade students participated in extracurricular activities, and those who participated in the painting group accounted for 1/6 of the whole grade, and 30 people participated in the calligraphy group, which was 20% more than the painting group. How many people are there in the sixth grade?
六年级同学参加课外活动，参加绘画小组的占全年级的(1/6)，参加书法小组的有30人，比绘画小组多20%．六年级一共有多少人？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

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

<gadget id="calculator">30 / (6/5) / (1/6)</gadget>
<output>150</output>

<result>150</result>