Arrange the marks in increasing order. we get,\\\\(22,24,25,26,26,27,27,28,28,29,31,32,32,33,35,35,36,36,37\\\\)Since, total no. of terms \\\\((n)=19\\\\)Upper quartile (Q3)\\\\(=3( \\cfrac {n+1}{4})^{th}\\\\)term \\\\(=3(\\cfrac {19+1}{4})^{th}\\\\)term \\\\(=3\ imes 5=15^{th}\\\\)term\\\\(=35\\\\)