There are 1200 people in the school, the first grade is 1/6 of the whole school, the sixth grade is 90% of the first grade, how many people are there in the sixth grade.
学校有1200人，一年级是全校人数的(1/6)，六年级是一年级人数的90%，六年级有多少人．
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">1_200 * (1/6) * (9/10)</gadget>
<output>180</output>

<result>180</result>