Students of Yuhong Primary School visited the agricultural exhibition. They are arranged in 4 rows with the same number of people in each row. Xiaoli is in the second row, the 9th person from the front and the 11th person from the back. How many people visited the exhibition?
育红小学学生参观农业展览．他们排成4行，每行人数同样多．小丽排在第2行，从前数是第9人，从后数是第11人．参观展览的一共有多少人．
<gadget id="calculator">11 - 1</gadget>
<output>10</output>

<gadget id="calculator">9 + 10</gadget>
<output>19</output>

<gadget id="calculator">19 * 4</gadget>
<output>76</output>

<result>76</result>