The students lined up, 19 boys stood in each row, 7 rows in total, and 9 rows of girls, 277 boys and girls in total. How many girls stand in each row?
同学们排队，男生每行站19人，共站了7行，女生一共站了9行，男、女生共277人．女生每行站多少人？
<gadget id="calculator">19 * 7</gadget>
<output>133</output>

<gadget id="calculator">277 - 133</gadget>
<output>144</output>

<gadget id="calculator">144 / 9</gadget>
<output>16</output>

<result>16</result>