we know that $1290 is to be divided on a 7:8 ratio, so we'll start off by dividing 1290 by (7+8) and give each person accordingly
[tex]1290~~ at~~ 7:8\implies 7\cdot \cfrac{1290}{7+8}~~ :~~8\cdot \cfrac{1290}{7+8} \\\\\\ 7\cdot 86~~:~~8\cdot 86\implies 602~~ :~~688[/tex]
