The ratio of the number of students in the morning shift and the afternoon shift of a school was 13 : 9. After 'n' students moved from the morning shift to the afternoon shift, the said ratio became 19 : 14. Now 153 new students sought admission in the school, and these students joined the morning and the afternoon shifts in the ratio 6 : 11 respectively. If the ratio of the number of students in the morning shift and the afternoon shift of the school after the new admissions became 24 : 19, find the value of 'n'.